I've heard goos things about the Magnum Four Strokes. I have two of the Thunder Tiger 54 four strokes, and they have decent power and are very reliable. One of mine has about 30 flights on it now, and is really beginning to come up on the power curve. It will give decent vertial performance on my 40 size Super Sportster. (Nice large, round loops. ) Even runs very reliably during extended inverted flights. (3 to 4 minutes at a time.)

I'd also suggest looking at a computer radio if the one you mentioned isn't. You may want to try Flaperons with the Cub and will need the mixing function.
Dennis-