I'll second the OS .46 AX. I only started flying last fall and the used Kadet LT40 I purchased to train on came equipped with an almost new .46AX. It is a powerhouse and I'm currently swinging a 12/6 prop and though we haven't tached it, it will still climb unlimited at nearly vertical. That engine needed almost no adjustment as the temperatures swung from summer into winter and it has never failed in flight. One of the seasoned instructors at our field was so impressed with the performance that he bought one for an ARF he was assembling and is having similar results.

Neal