Hey, believe it or not, these are the same servos I used on the $50 bot.
No complaints (suprising), but I do have some pointers when it comes to modding them:
They have metal gears, and a metal pin to stop rotation. it is a mother to take out, but after some time with some needle nose and some elbow grease, they pop right out.
Also, the ball bearing inside the main gear is holding in the plastic piece that turns the pot. I couldnt get either out (the plastic piece or the bearing... looking back on it Im glad I didnt get the bearing out - would never have gotten it back in), so on the first one I melted out the plastic part with a soldering iron. I realized this was stupid and messy and on the second I just clipped off the pot head with a pair of wire cutters and glued the rest in place.