I'll throw another mention in for Thunder Tiger's outstanding GP-42 plain bearing engine. Most pilots think plain bearing engines are weak because they've only tried O.S. Max LA series engines. The .46 LA isn't too bad, but the old .40 LA from O.S. Max almost single handedly turned a whole generation of pilots off of plain bearing engines.

The GP-42 is dead solid reliable, durable, and easy to tune. It's similar in power to many other sport engines in the .40 ~ .46 size range. Plain bearing engines like the GP-42 have no ball bearings to rust so they require very little effort to maintain them and they're a great choice for seaplanes and float flying.

Many .40-size trainer ARFs fly better with lighter weight engines and may tend to land faster and heavier with a ball bearing .46 two stroke.

Good luck and good shopping!