TC3 would make a real deluxe controllable drifter, I set my race car up for drifting and it is way more fun to drive than my TL01 - but I don't want to bash on the race car so I still use the TL01 for drifting. The T-Spec is a good car, it isn't as good of a race car as a TC3 but I think it would make a much more controllable and smoother drifter than the TL01 or TT01. If you're willing to spend a little more than what a Tamiya car costs I would go with the T-Spec since if you get sick of drifting and want to take it to the track you'll still have a car that will be fun to race.

The only real downside I see to the T-Spec at the moment is lack of parts available. If you blow a outdrive it's hard to pick one up at the LHS - at least around here. Nobody sells T-Spec parts yet in my area, but at the same time less hobby shops are carrying the now aging Tamiya parts.