I've been doing some research on the Katana ( most likely my next plane) and on Precision Aero's website they have a link th rc groups thread. It's quite extensive and there are alot of recommended power set-up but the one caught my eye which the link sends you to e-flightline's websight and there videos. They show there best set-ups for the Katana. One was the 2015-5300 with 1320s and was great but not a ton of power. The preferred set-up was the 2025-5300 and TP2100 prolites, all used the cobri gearbox 6.3:1. Not that an outrunnner is a bad choice. I think they're are a bit bias sense they make the cobri gearboxes as well

Just more food for thought, and just my opinion, too.

Good Luck

Jay

http://www.e-flightline.com/movie.htm