You can't go wrong with a Goldberg model, Kit or ARF. I don't have a Decathlon but I've seen plenty of CG Decathlons, there's a couple at my club flying with 91Four Strokers and believe me they're plenty of power for this airplane. If you go with a 1.20 I think you're going to find yourself throttling back a lot. You just don't need that much power for this airplane! Good Luck!