RE: Foam vs rubber wheels?
Another factor to consider is the surface you fly off of. If you're flying off of asphalt foam wheels usually won't last long. The hard surface will tear them up pretty quickly.
I just finished reviewing the Top Flite B-25 which included foam wheels. I have to admit that I was a bit disappointed that a $600 plane included cheap foam wheels. I would have rather seen them use rubber wheels.
Ken