[Dave Campbell]

I have 16 VEX kits in my lab and I am finding that most of the same problems - Motor wire pins breaking very often is my biggest complaint. We have them stored neatly and the students take fairly good care of the parts. The pins are just brittle. I have not had the gears break, but the clutches seem to round out with the pins or square shafts. I attribute this to the screws loosening either on the motors or on the frame and slightly disengaging the shafts from the clutches.
All problems aside, I still like the VEX kits over Tetrix and LEGO. I have a few of each of those other kits and the VEX kits offer more flexibility with differentiating the instruction for the students. From basic machines- levers, inclined planes, etc, to programming complex autonomous machines.
I will be fixing about 8 to 10 motor wires each quarter, but I have bought pins and can salvage what I need easier than returning the motors to VEX for repair or replacement.
Best of luck with your decision.