Think I'm going with the 4325-425 6s5300 geko 125 d771 combo
Sounds like a winner to me. Never used those servos, but everything else should be great from what I've seen. Specs on the d771's look like plenty of power.
I have a pretty good gas setup on my RCGF 26cc. Having said that I would do it electric next time around. My current one is a little too gunked up from the gasser for my tastes. I am trending back towards electric anyways.