RE: When do I graduate from the trainer???
A lot of great advice here. 2 years ago I used Real Flight to train myself and used no instructor to learn on glow. I flew my trainer (tower trainer 40) for about 2 months before It felt to restrictive for me and I upgraded to a basic semi-sym. low wing bird. I too revisit my trainer for basic re-fresh, especially if I have been away from flying for a few months. (like now). I have since started to explore 3D but sport/pattern flying is what I like.
Bottom line is if you feel comfortable with upgrading then do it!
Good luck!