I grew up with these cars and love 'em!
The 225 is a full-size GM battleship - same basic car as the Olds 98 and Caddy Sedan de Ville. A '72 should have the 455 Buick V-8 and THM400 automatic, as well as power windows, locks and three-across bench seats.
The Ups:
Great style; no new car has he presence these cars have;
Super roomy/comfortable; six adults can ride;
Easy to work on; no computers, simple as it gets;
Parts abundant and inexpensive; huge aftermarket support exists;
Smooth ride; nothing like it.
Still very affordable; you can buy a cherry '70s-era large sedan for less than $10k.
Good investment, probably; values have nowhere to go but up.
The Downs:
These are huge vehicles; most people younger than 40 have no clue. Some push 20 feet long. They will eat up even a large garage (and may not fit in a garage built since the '90s, which assumes modern - smaller - vehicles. (Last summer, I looked at and almost bought a '75 Caddy Fleetwood d'elegance. But I held off because the thing was so huge it would literally have just barely fit in the garage, leaving almost no space even to walk by it. )
They can be intimidating to drive/park.
Massive gas guzzlers. Mid-high teens is typical. Most have 22-25 gallon tanks, like a current full-size SUV. So cost about $60 to fill up. Many need premium unleaded.
By modern standards, brakes are atrocious; these things corner like Winnebagos.
Rust-prone bodies; if it gets wet routinely or is ever driven in winter, rust will be an issue.
Requires more frequent minor "fiddling" - with the carb/ignition especially - to stay in good running tune. It's no big deal if you can do this yourself but is a hassle if you can't.