freebird1 have you seen the last video post I posted on the thread, personnaly the DA50 with a 23x8 prop is more then enough power to handle this plane, if you need the extrem pull out speed put a 22x10 or maybe a 22x8 on there and you will notice a vast improvement.

You can even shave off weight from the plane by replacing the landing gear and the wing tube. I have personnaly never used a SPE engines, mainly working with Da's and 3W's. I have also heared good feedback from corona engines (sp?). Or maybe even consider the zdz60.