The answer depends in part on the layout of your flying field. The Sig LT-40 is a superb trainer; my club is on its third LT-40 club trainer. It's a bit of a floater, though, so if your flying field is cramped you might do better with something a little smaller and with a bit higher wing loading. (My favorite in this regard is the Midwest Aerostar 40, which, alas, is no longer being made. It turns a little quicker and comes down a shade faster than the LT-40.)

As the previous post said, though, there are a lot of good trainers, and getting any of them would not be a big mistake.