I fly a DPM Edge right now on a DL 50. Bought a Moki 2.10 for it to start as Dave Patrick was so adamantly against gas on this airframe. I made sure the motor box was glued very well, and it has been perfectly fine with gas. Keep in mind I am used to SEVERLY overpowered planes and don't fly fast downlines and rarely hit WOT unless vertical.
Mine is kind of done in overkill style. 7955's Aileron and Rudder. 5985's on Elevators. In the early days people were blowing the ailerons off this plane due to flutter, poor servo choice, and poor set up. So I put the good stuff there. All servos are in the tail to balance the DL.
Mine is running a single pack of A123's feeding a AR9100 and the ignition. About 3/4 down to the first tail former for a neutral CG. No Spinner, No pants, Xoar 23x8. DA muffler. Just a shade under 14.5 lbs. Flies great if you keep the weight down. Mine is a big baby, but I've seen them loaded up to be tippy rocks.
CG on the Extra is between 5-6". Here is a link.
http://www.davepatrickmodels.com/dpm/extra/cg_fix.htm
Good luck.
Mike