I have an '01 Spyder. the VVTi is a good engine, but the car is still under powered. 138hp/125 Tq. there's quite a bit of aftermarket stuff for them now-turbo kits, body kits, intakes, exhausts, valves,injectors, suspension,etc. but when i came across a used '91 MR2 turbo , I picked it up and still kept my Spyder but stopped at where I was with the mods. The Turbo has so much more potential than the spyder. With minimal mods you can get 50 to 70% more hp in the '91 turbo. I do think the Spyder handles better but I really like the turbo more. heres a link to what I've done to both. turbo wins - hands down
http://members.cardomain.com/mr2bad