for $40-50K you could pick up a clean Gen3 viper or a 2006 viper coupe with a fw miles on it. although by all means go GTS if you prefer them (i did).

I'd take a viper of some kind over all the other cars you mentioned. i dont like cars with to many models (C6, C6 Z06, C6 ZR1...or 911, 911c4, 911c4s, 911turbo, 911turboS, 911gt3, 911gt3rs, 911gt2 and lets face it boxer and caymans look pretty much the same too when there coming down the freeway at you)...i'll take low production numbers and one model design any day.