The OS LA may have been the wrong choice in the end for this model, but hindsight is a woundelful thing. The LA series are however a very GOOD motor. They are not designed to have the power of a FX or AX type. That is why OS also make those. I have been using the OS 46LA for some years, the only thing you need to do is tigten up the back plate screws every few months. It is a perfect choice for a slightly lighter model, they have good idle/throttle response and are cheap. I use one in a scratch build KAOS40 and it is perfect for the sports flying that I do in it.