I had my .40-sized one out today. I've had some teething problems with the OS .52 / YS .53 swap but finally got them straightened out today. The tank was leaking pressure, so the engine was dying after a fairly short period of time.

It is Faster, as I expected. With an 11x7 prop I'm getting 10,700 on the ground... on downwing WOT passes it unloaded and sounded like it was running north of 12K. Throttled back in a hurry - I'd hate to blow the motor up.

Weird: Came in for a normal landing. Rolled to a stop while holding full up elevator (to keep the tail down.) Killed the engine, then walked out to retrieve it. Noticed that the elevator was still deflected full-up, and didn't respond to radio inputs. The elevator servo died during the rollout!

Weird #2: While carrying the bird back to the pits, the elevator servo went "zip!" and started working again. Need I say that I didn't put the plane up again?

I have FMA coreless servos installed in this bird, and this is the second one that has failed. The first one was the rudder servo which let go in the air about ten flights ago - one of the wires going to the motor broke loose due to vibration I pulled the servo, replaced the broken wire and potted the remainder with RTV.

/me thinks I need to do the rest of them...