Lol They are COMPLETELY different vehicles.

RSX-S is a sport compact, it's sporty but will never be a sports car due to it's FWD.

IS300 turbo'ed can be real quick, but it would never outhandle an S2000.

IS300 would be the most comfortable out of the bunch, the S2000 would offer the most performance. On a track the S2k will smoke both no problems.

But you also lose 2 seats. And forget about winter driving. It's up to you really. The RSX-S can be modded to go fast, but it's still a dressed up compact. You can never get away from it's FWD. However, it can be quite practical, decent sized trunk and slap on some winter tires and it'll be ok in winter.