3 years ago I bought a Magnum .15 xl for A class combat. It is not as powerful as the RJL or maybe the new O.S. but here it is 3 years later, and it hasn't missed a beat. It has started and ran perfectly and solidly in every heat every month since new and still as powerful as the first season. It has been dirtnapped more time than I can remember and nothing on it has broken yet. Just today Sassy broke in a brand new Mag .15 Xl for her A class combat plane. Break-in is complete and it runs perfect from the first flip. Good strong little engine, and if it's anything like mine, it will be that way for a long time!