I have a VTS, (Used to have a VTR) and they aint slow once you get them above 5000rpm and they come on cam, (They redline at 7000rpm, hit the limiter at 7500rpm.) At lower revs they feel pretty uninspiring but once you hit the sweet spot they transform into a bit of an animal
I have yet to race a 16v or 106Gti, but from what people have said there shouldnt be much in it on the straights or twisties. Some people prefer the exclusivity of the GTi, some prefer the looks of the VTS. Everyones opion is their own.
The back end can be a little lary unless you are good at lift off oversteer be carefull with the VTS/GTi on bends, dont even think about backing off at speed!
But although they can be a handful when abused on a bend it really gives a feeling of acomplishment if you do take a good corner, they can really reward good driving but they can punish the unwary, which is why most totalled VTR/VTS/GTis are from spotty oiks that have only been driving 10 minutes!
I dont think they are anywhere near as fast as a 172 but for the money they cost they are good value for money with more modded bits and pieces than you can shake an induction kit at. And they are still faster than 90% of the cars on the road
Just dont try a rolling 50mph start against a Saab 93 turbo as I found out to my suprise!