I just did what you are planning to do, using the AMR 20 trainer and a DLE 20. Since I'm still fairly new to gas engines, I ran a couple of tanks through it, then had an experienced gas engine friend check my needle settings. After we were convinced the motor was a little rich on the low end and just breaking into a 2 cycle on the high end, we flew it. The DLE 20 had way more power than the AMR 20 trainer needed, and the 16x8 Xoar prop wasn't quite enough (17x6 would be better). Make sure your needle settings are good, run a couple of tanks through it, and go fly. Unless you want a gas goof-off plane like I did, trainers aren't necessary for the DLE 20.