I'd like to help but this is my first gas plane also. I know with my (generally overpowered) nitro models, I've been able to run them in while in the air as I've always been able to break them in while I fly as I only have them at only about 1/2 throttle for general flight.
I would start by ground running just to get the low and high speed needles set as best as possible before setting off, if nothing else.
Let us know how you end up post your maiden.