Parts on the way. I've debriefed myself on the bad flight, and have come up with a few error points to avoid.
1) Don't fly in winds over 5 mph until my flight precision improves quite a bit. (Wind was about 10 mph and was a factor in the distance.)
2) Don't fly into the half of the sky's hemisphere that the sun occupies. (Although I wasn't blinded, the sun was backlighting the heli, and the silhouette effect contributed to the disorientation.)
3) Don't let the heli get more than about 30 yards away, unless most of the distance is altitude.

I still don't understand some of the trouble with that gyro. I admit that I have to very slightly "mind the tail" in a hover, but the drift seems to be linked to my cyclic corrections in some way. It's not a constant drift, and I only occassionally have to correct about 3 to 5 degrees or so. This is the very first I've heard about the capacitor, and I've been monitoring quite a few Axe 400 threads on various forums.