I wouldn't recommend the TC4 now, but not for the reasons BeeMain stated.
I've ran the FTTC4 for two years. Never had handling or breakage issues. One other guy at my track ran one as well, and he kicked butt in stock rubber and 19t classes. I did OK, but this kid showed the cars potential.
They're not making all of the replacement parts anymore, and there's not going to be a lot of help for you with setup questions, other than online.
If budget is your main concern you are probably stuck with a used older model. No matter what you choose, parts may be an issue. With any luck, at least most LHS's have/had a decent stock of TC4 parts.
check you local shops and ask what they still have for what cars.