pretty much any generation m3 is going to be an extremely fun car to drive. more specific questions and i'll at least try to help.

As far as forced induction if you are looking to build high horsepower the e36 m3 is probably better due to the lower compression ratio. Active Autowerkes has produced a supercharger kit for the e46 m3 that when coupled with a little nitrous produced right around 500hp. I want to say sans nitrous it is around 440 crank horsepower. There are many turbo/sc options for the e36.

As far as reliability there aren't too many high mileage e46 m3's running around but one of my best friends bought his 2001 m3 cab new and had no problems until now (65k miles). The e36 m3 motors (s50/s52) have proven to be pretty reliable. They are generally good for 150k+ without problems.

Main con is that parts are expensive for the cars and therefore they can get a bit pricey to maintain.