If you're talking about an M3...

and if you're looking for an old school (relatively) sports car with direct control, direct feedback and handling that's true to the fundamentals.. a lot of enthusiasts consider E30 M3 to be among the best.  I would tend to agree.  And it does feel quite different from modern cars.  It's light weight too.  But compared to modern cars, the lack of power is quite a big turn off for me.  Afterall power is a very big part of being a sports car.  Also, a four cylinder engine is simply no match for the newer I-6 (let alone the latest V8) in sound quality.  The sound of the engine, again, is quite essential to the enjoyment of a sports car.  Besides, like you've noticed, they are all really old.  Unless you're looking for a very cheap car good enough to race (risk) with, I would get something newer.  E36 still has pretty raw old school handling, but with a nice I-6.  It does look ugly :-(