I got a chance to fly one of these yaks the other day. Im quite impressed with the kit.
And it flys pretty well.

I however am not in the least impressed with the park 370 gearbox set-up that they recommend. That park 370 brushless (while it has TONS of power) gets absolutely blistering hot even on a short run. I've recently flown this setup not only in the yak, but also in a tribute 3d. Both of them get so hot you cant touch the motor.

Both are swinging the recommended 12x6 prop. What are you guys doing to keep them cool? Heatsink? Undersized prop?