I have been looking for a nice TC4 also but they are kinda hard to find nice ones for the cheap. In fact I was shopping the TC5 simply b/c the part support would be easier and they seem to come way down in price. I want a 100+ mph sedan too.
As far as maitanance I dunno, but for speed they are soooo capable of over 100 with MM and 4s!! I wanna but its going to have to wait till after the 8ight.