Here's a good read on the HXT900's. [link=http://www.rcgroups.com/forums/showthread.php?t=923175&highlight=hxt900]HXT900 Test Thread RCG [/link]

I know the test pilot, GunnyGlow, personally. While it would be a stretch to say these servo's are as good as the Hitec HS65's he was quite impressed with these little guys.

And at $4 each, why bother changing stripped gears?
Just throw away the bad servo and replace it with a new one.

BTW, you can get the HS65HB's from www.centralhobbies.com for $19.99 ea.

EDIT: Forgot to mention, the review by Gunny is post #40.