Bang for the buck for fun
Steve,
If you intend to use the airplane only for fun and self improvement, then you really can't go wrong with the OS160.
For the sport flyer it has several advantages as follows:
1. Inexpensive
2. Runs nicely on 5-10% nitro
3. Is happy with a full length muffler instead of a tuned pipe resulting in no a hassle, non-peaky motor.
4. Is not more difficult to tune than a OS.46FX.
Personally, I run the OS140EFI and the YS140DZ, but the OS160 is right behind them, especially when hooked up with the Cline Regulator.
Mark