RE: Is the Avistar an OK Trainer?
Avistar would be fine. It is very stable and will slow down nicely, and in my opinion handles wind better than a flat bottom wing trainer. Get the RTF version, don't pay attention to the bad things you hear about the .40 LA. It's a great engine for this plane... plenty of power. Later you can switch to a more powerfull engine and really explore the plane's handling potential.
My five cents...
Andy