BMW sport sedans are still very much the "ultimate driving machines." It's just a shame you have to fight with a lot of often very frustrating technology while you try to drive the things.

The '08 5-Series, for example, is without question the most powerful (and quickest/fastest) regular production 5-Series sedan BMW has ever offered. For the new model year, it has been updated with a larger, 3-liter, 230 horsepower version of the famous DOHC in-line six now standard in the base 528i ($44,300) and a new-for-2008 twin-turbo version of the 3 liter six that produces 300 horsepower in the mid-range 535i ($49,400). The top 5-Series engine is a 4.8 liter, 360 horsepower V-8 in the 550i ($58,500) that delivers 0-60 runs in the 5.5-5.6 second range.

All three engines are formidable performers that seem to enjoy being run hard - especially the two in-line sixes. And the new twin-turbo version of the 3-liter engine delivers the level of output and acceleration capability you used to have to upgrade to an M-spec BMW to get. You can still get a manual transmission with the V-8, too. Virtually all the other so-called "sport sedans" these days are automatic-only deals. And the few that aren't (for example, the Nissan Altima) don't have the BMW's upmarket cachet - or the eight cylinders.

Wagon versions are available as well.

The rest of the 5-Series' driveline and chassis is equally commendable. Whether you choose the hammer down, throttle oversteer and burnout-friendly hooliganism of the rear-drive 528i, 535i or 550i - or the more responsible power delivery of the AWD-equipped 528xi ($46,500) and 535xi ($51,600), there are few cars with four doors that can match the Beemer's yin-yang balance of track-ready handling precision and right-now responsiveness with a ride that's supple yet not overly firm. To drive a BMW is to forever look down upon lesser machines.

Ok, now for the ugly stuff.

Much has already been written about BMW's notorious iDrive system, which uses a mouse-like button on the center console to access and (in theory) operate various functions, such as the GPS, audio and climate control. To say it's exasperating and needlessly complicated would be unfair. Not to BMW - to the prospective buyer. Because that's soft-pedaling it. The system is fussy, a challenge to navigate through even when the car's not moving - and is the equivalent, in terms of how it affects the overall driving experience, of finding a curly pube floating in your otherwise 5 Star serving of snapper soup.

BMW has, at least, "simplified" the layout for '08 by incorporating redundant secondary controls of the old-fashioned (and easy to use) rotary knob type for a few essentials like adjusting the temperature of the AC/heater and fan speed - as well as a few pre-programmable Memory functions. But to use the GPS - or manipulate the stereo system - you'll still have to wade through the iDrive.

They say you get used to it - but that doesn't make it any better. Be absolutely sure you can live with iDrive - before you drive the car home.

Another area of pointless techno-creep is the "e-shifter" for automatic-equipped models. Instead of the usual console-mounted handle you move from Park to Drive, you now have what amounts to an IKEA-looking electric toggle switch - including a button on the top to engage the parking brake. No more manual lever to pull and release - which is probably fine - until the warranty runs out, the electric circuitry and actuators fails and you're faced with a non-working parking brake - and a big repair bill.

But the underlying question is, why is any of this necessary? Or even helpful? What is wrong with a mechanical parking brake lever? It is simple, reliable, does the job perfectly well - and requires no elaborate components that will be more prone to fail and cost you money and hassle down the road. And the e-shifter? You have to tap the toggle just so to get Reverse instead of Neutral - or Drive instead of Reverse. Worse, it gives you no tactile sensation you've moved from one gear/range to another. To know for sure where you are, you must watch the little digital lights illuminate. Like the iDrive controller, the thing merely duplicates a function more efficiently handled by a simpler, less hassle-prone device. There's no good reason for it - or for iDrive - other than to demonstrate that there are more complicated and expensive ways of doing things.

But more complicated and expensive is not necessarily an improvement. Especially when the car involved is built for the person who enjoys the experience of driving - not being thrice-removed from it via over-smart gizmos that pre-empt and usurp him.

These defects inflict more psychic pain than an ugly, extruded plastic GM interior (what were you expecting?) since the rest of the car is so damn good. It's like dating a supermodel who also happens to have a really grating helium voice - or suffering an insolent waiter at your favorite restaurant.

Happily, you can dodge the e-shifter by sticking with the six-speed manual transmission - which makes the car a to more fun to drive anyhow. And if you have to have the Steptronic six-speed automatic, there's still some hope. BMW has added a Sport version of its six-speed automatic (available on the 535i and V-8 550i) which includes steering wheel-mounted paddle shifters that let you avoid the numb-feeling e-shifter on the console.

Unfortunately, there's no getting around iDrive - if you want an '08 5-Series, anyhow. The system is standard - and unavoidable - in all models, from base 528s through the top-of-the-line V-8 540i.

It's sad BMW continues to try to force acceptance of its not-great-idea rather than admit the mistake and redesign the interface to be usable without having to "scroll through menus" or risk crumpling the sheetmetal or having a stroke triggered by sheer exasperation.

Especially since the cars so hobbled are otherwise so appealing.