RE: Carbon gear servos
I have karbonite gears on many of my aircraft servos. They do not strip nearly as easily as the whit nylon.
I had a set on a 73" cap that went in due to some radio interferance (the only plane I ever lost to such a thing). The plane was totalled, but the servos were fine. I put them in a replacement cap (exact same h-9 arf). They are still operating just fine.
I have heard some of the "horror stories" of people's karbonite gears snapping if they looked at them wrong or if the stars were not in the correct alignment, but my experience has been otherwise.