Never buy a car on looks alone.

Sexy bodywork could blind you to the realities of Hummer-like fuel economy - or a kidney-killing ride. Just as you'd take a wider view about the person you might want to marry, it's important to consider the whole package before deciding whether to bring home that four-wheeled-honey.

Here are a few things to put on your Real World Test-Drive Checklist:

* Does the car fit not just you but everyone who will be a regular driver/passenger? -

It's obvious that you should be comfortable getting in and out, that the seats feel good to you, that the ride is right - for you. And so on. What's not so obvious to many car shoppers with wives/husbands/kids is that the prospective vehicle ought to make them happy, too.

Or at least, it shouldn't be The Car Everyone Else Hates.

If your wife/husband/SO will be using or regularly riding in the vehicle, be sure they come along for the test drive and also feel comfortable getting into and out of the vehicle, are ok with the general layout and don't have any major objections to it. If you have teenagers who'll be carted around in the vehicle, check that the back seats are sufficiently roomy. If older (especially elderly) people will be frequent passengers, be sure the step-in height and roofline aren't going to be obstacles for them.

Bottom line: Don't forget to take into account how others will react to the vehicle or you may never hear the end of it.

* Controls -

How easy is it to change the radio station and adjust the climate control system while the vehicle is moving, in traffic - without actually looking at them?

In many new vehicles, you'll find that individual controls (knobs and switches) for each feature have been replaced by a single integrated multi-function controller, often a mouse-like device, that can be both awkward and intimidating to operate. High-tech stuff can be cool, but be sure you can comfortably and easily operate all the features of your next vehicle without having to take your eyes off the road - or fumble with complicated controls. And again: If someone else will need to use the vehicle regularly, be sure they can deal with the controls, too. Remember that older drivers may have problems with small buttons - or fonts/type size (such as the readouts on the gauges) that may be harder to read for people with less-than-perfect vision.

* Situational Awareness -

Some vehicles have show-car looks - and terrible blind spots - making it hard for you to keep track of what's around you (or even to know it's there). The key thing here is that blind spots can be a function of your body type as much as the bodywork of the car. For instance, driver with long legs may have to push the seat back to comfortably operate the pedals, but as a result, the seat is now a lot closer to the "B" pillar just aft of the driver's side door glass - which can make it hard to see other cars rolling up on the left. Many new cars also have sharply raked windshields, low-cut rooflines and relatively small rear glass, which looks great from the outside but can also make it harder to see other cars around you. Similarly, with some vehicles, it's hard to get a sense of where the front end ends because of the way the bodywork drops off - making it unpleasant to park the thing and all-too-easy to bump into other cars. A test drive will let you see whether - with the seat adjusted for your body type - you can clearly see to the side and behind you. And by actually trying to park the car out in the real world, on public streets, you'll be able to see whether you can do that comfortably - and without risking becoming your bodyshop's new best customer.

* Standard vs. optional engines -

Many new vehicles offer more than one engine choice. It's important to try out all the possible combinations, especially when it comes to four-cylinder vs. optional V-6 and standard V-6 vs. optional V-8.

If you haven't been in the new car market for awhile, you may not realize that today's four-cylinder engines often make as much power as the V-6 engines of 10 or 20 years ago, while modern V-6 engines often make as much (or more) power than V-8s used to. What this means is you may not need to pony up the extra coin for an optional engine - which will also usually use more gas, too.

Just to give you a case in point: I recently test drove a '2010 Nissan Altima 3.5 SR. This is a modestly priced (about $24k) mid-sized, family-type sedan. But its 3.5 liter V-6 produces 270 hp, which is something like 30 more hp than a mid-late 1980s-era Corvette with a 5.7 liter V-8 was putting out. The Altima V-6 can reach 60 mph in less than 7 seconds - which is quicker than my '70s-era muscle car, a 1976 Trans-Am with 455 (7.5 liter) V-8! And the 2010 Altima's performance is typical for a current-year V-6 family-type sedan.

It's great fun, of course - but the point is you may not need a car that can burn rubber like that. The standard four-cylinder engine (175 horsepower in the '10 Altima) could be enough for your purposes.

A test drive will tell you - and might just save you thousands up front (and at the pump).

* Transmissions -

There are more transmissions choices today than many people realize: conventional (hydraulic) automatic, Continuously Variable (CVT) automatic, dual-clutch/"sequential" automatic; standard manual with a clutch, clutchless Direct Shift Gearbox - just to name the majors. You'll find that many new car models offer a choice of two or even three different transmissions and each one will have its pros and its cons - and behave differently. CVT automatics, for example, are becoming very popular because they offer the fuel efficiency advantage of a manual transmission with the convenience of an automatic. But they can also be noisy (relative to a conventional automatic) and their "stepless" operating characteristics (no up or downshifts; just a single forward speed) might not be for you. Similarly, some of the automatic clutch manuals (a true manual transmission but with the clutchwork handled automatically, by electronics) can be lurchy. Clutch take-up on (how quickly/smoothly the clutch engages) on standard manual models with a driver-operated clutch can be a crucial factor in terms of everyday livability, especially in stop-and-go traffic.

You should try to sample each type of transmission available in the particular model of car you're considering - and under the driving conditions that are normal for the type of driving you do (such as low-speed commuting, for example - or high-speed highway driving). With manuals, especially, be sure the clutch/shift action are in your comfort zone. If it's a regular automatic with multiple modes, have the salesman explain the operation of each setting and be sure try them all out to get a feel for how shift quality changes in "normal" vs. "sport" and so on.

Bottom line: Everyone has a different style of driving and there's no one "best" or "right" type of transmission - as far as what's right for you. The only way to find out is by actually driving the car, out in the real world. For example, the typical 1-3 mpg fuel economy advantage of a CVT over a regular automatic may not be worth the increase in driveline noise that sometimes comes with a CVT. Or, maybe you'll find after a test drive that as much as you like the idea of a manual transmission, it turns out the automatic's more pleasant to drive.

* Real-world performance -

You can look up the 0-60 times and top speeds of any car but you won't get a feel for how the car actually performs for you, the way you drive it, until you get behind the wheel and try it out for yourself. Some cars have engines that look great on paper because they produce high power - but only at higher engine speeds. Honda's S2000 sports car comes to mind. The S2000 is a great track-day car but it's a beast to drive in stop-and-go traffic, because it has very poor low-end power. It's the kind of thing you'd only discover by actually driving the car.

The main things you want to establish are that the vehicle has enough power to comfortably keep up with traffic at the pace you normally drive; that it can pass slower-moving cars and pull onto the freeway and merge without it feeling like a close call.

Take the vehicle out onto the highway and get up to the cruising speed you usually maintain. Does the engine feel like it's working too hard? Is it noisier than you'd like? Be sure to include some uphill driving on your test drive route and if you often drive with a passenger (or passengers) on board, be sure to bring them along for the test drive. Remember: Each person adds their body weight to the car's curb weight - and if it's two big guys, that can easily mean an extra 400 pounds the engine has to lug around. A vehicle that might accelerate adequately with just you in it (or on flat roads) might slip down to inadequate with two or three people inside - or when trying to climb a grade.

As far as handling/braking: Because of the tremendous advances that have been made during the past 20 years in everything from tire design to active/passive technologies such as ABS and stability control, any new car you shop will handle/stop at a level that's acceptable for everyday driving. Some cars offer much more than that, of course - but it's not like it used to be when some new cars were actually borderline dangerous or noticeably inferior on either score. So, when it comes to handling and braking (and also ride quality), the main thing that matters is how the car feels to you. Not to some road-test reviewer in a magazine tossing the thing through an autocross.

* Real world gas mileage -

Don't assume the fuel economy figures listed on the window sticker represent the actual mileage you will get. The government tests new cars and trucks to get an "average" city/highway fuel economy figure - but the government's test loop may not reflect the type of driving you do. If, for example, you drive more aggressively than the testers did - your actual fuel economy is likely to be significantly lower than the government's rating. You may also regularly carry passengers - or a heavy load. These variables will affect the actual mileage you get. Never assume that the advertised 18-mpg rating (as an example) is what you will get. Read the fine print. The EPA even says "your mileage may vary."

Trust me - it will.

If you are budgeting a certain amount for gas bills each month, based on the advertised fuel efficiency, you could find yourself paying more than you expected. Once again, the test drive offers salvation - or at least, an important insight. An easy way to check the actual mileage with you behind the wheel, driving the way you usually do, is to zero the car's trip meter before and fill the car's tank at the start of your test drive, then fill it up again at the end, noting your mileage on the trip meter. Now you can do the math - and get a very good estimate of the car's real-world gas mileage.

* On the road ergonomics -

This last item may the most important. Seats that may feel perfect in the showroom might be murder on your backside after 30 minutes. Driveline noises (and wind noise, etc. from outside) you might never have noticed during a 10 minute putt-putt around the block may get on your nerves once you're on the highway. A ride that feels great on the near-perfect asphalt close to the dealership could prove overly firm (or too soft and bouncy) on less-than-perfect roads. You should test drive any car you're serious about buying for at least an hour, on all the types of roads and under all the conditions you typically deal with every day.

Anything less is like buying a house on the Internet and hoping it's going to be right for you.