My .61's are real runners. My 1.20 took awhile to break in but now runs very well on 5% nitro (Cheap!). My buddy has a .46 he rebuilt after tossing a rod (many hours of time) and folded the wings on his Telemaster .40 with it! The carbs are the only real problem, they are good or bad no in between. They also tend to leak a little. Keeping the o-rings replaced solves this though.