I also have the H9 cub. I have a Supertiger 45 in mine, and that is lots of power for a cub. 4 stoke would be a lot nicer sound. This is the second H9 ARF i have bought. I also have a H9 P51 PTS trainer with a ST 51. I do have one issue, and part of it is because I didn't know better, you kinda learn as you go with this sport somtimes but these forums really help. The plastic Kwik Link connectors that come with the H9 kits can be a problem for the beginner. I had one of these fail in flight on an aileron. I was able to land the plane after some tense moments to say the least. The small plastic pin was still in the control horn but broke out of the kwik link connector. I feel that I caussed the plastic fatigue during set up. Care needs to be taken not to put any stress on these pins during opening or closing the link or just pushing the pin through the horn holes. I have since changed all my models to metal clevises with metal retainer clips just to be safe. Both my H9 planes fly well and look good to boot. Recently I set my cub up with flapperons, but have not had a chance to try it yet. Maybe spoilerons would be better to get this bird to stop floating.