Ok thanks guys. So I'll order the 12.25 and 12x4 I guess as well. Try both.

The 46AX is new, but I'll be running it on another plane with probably a 11x6 for about a month or so (initial break-in will be with 10x5 I guess). Only after that I'll put it on the GP Extra.

With the GP Extra I'll be more interested in climb and maneuverability than speed, so I'll experiment with the larger diameter props.

Thanks, clears that up. I can now focus on the remaining decisions related to the order.

Cheers

edit: It will have a 4 stroke on it later, but I'll make do with the 46AX for a while first.