ZDZ 80RV for a WildHare Edge 540T would be nuts and way overpowered. ZDZ 80RV is for a 22-25lb plane and that will give it unlimited vertical no problem.

DA-50 just like the older siblings are a great line of motors

ZDZ 50 is another great running motor

BME 50 with the new BME 55X coming sometime hopefully

Taurus 52cc is supposively the smoothest running gasser made and strong

3W 50

First Place Engines, FPE makes I believe a 40-50cc engine also

Much to choose but DA 50 pretty much tops the list