I don't know anything about the Tower trainer, but I personally have the Avistar Select and my club has 2 SuperStars as club trainers. These two planes are well put together, and quite durable. I personally have put my Avistar into a tree, and it is still flying after some minor repairs. The SuperStars I have seen tumble down the runway, and again a few quick repairs and they were back in the air.

I would second the statement that the .40 LA that comes with the Avistar is a little weak. However it seems to pull the Avistar around a little better than the SuperStar. The Avistar doesn't have much vertical with the supplied engine, but it can manage most basic aerobatics. However it is only after flying the plane for the last 4 months that I am starting to wish it had a bit more engine. I personally decided to go with a new plane instead, but an engine upgrade would be a nice boost.

If I had to make a suggestion I would go with either the Tower Trainer, or the Avistar. The Superstar is a lot like the Tower Trainer, only underpowered. Another options would be to get the Avistar ARF and buy the radio equipment separate. This way you can start out with a stronger engine.

No matter what though, if these are the 3 you are choosing from I don't think you can go wrong.

Good luck, and have fun!