I agree with big al. The TA05 is a sweet car. In capable hands, the chassis can keep up with the more expensive race sedans. Plus, if you have the choice between new and used, go with new. The TC4 is also a good choice. Some people dont feel it is a worthy contender since it is a shaft driven car and most of the professionals seem to be driving belt driven cars. The fact is, the TC4 is a race proven design that will not let you down. Maintanance on the TC4 will be a little less time consuming as you do not have to take the car apart to repair a belt. Also check with you LHS about parts availability. Make sure your shop has good part support for the car you decide to purchase. Take care and good luck.
llamont