Well, I personally probably won't buy l4d2 before it hits the bargain bin (I expect it to get boring faster than the first one) so I'm the wrong guy to talk to

In general I think T-Regs is not big enough for that (look at wdg's, where the community is much bigger. While I don't have any numbers, in my book it's hardly used. Update: If gametracker is correct, the server has been used two days in the last month (
http://www.gametracker.com/server_info/217.163.30.189:27015/ , hit the month button on the right))
Of course I can't speak for the entire group, but I doubt anybody would have a problem with you putting up a server labeling it T-Regs if that's what you want.