[BBray_T1296]

In 2011 we used the standard AM 6" mecanum wheels. In 2012, we used the HD wheels, due to the bump and related forces (even though after calculations, the standard wheel specs would not have been exceeded). After 2 regionals and an offseason, and extensive testing (our first year using mecanums) in 2011, we did not, and still to this day, have not replaced any of the rollers on the wheels. On our 2012 robot, after our 2nd regional we had to replace about 10 rollers, some from each of the 4 wheels. This was probably not due to any difference between the standard and HD wheels, but likely due to slight skidding on the ramps and testing on linoleum floors that wore down the rubber rollers over time.

I have not used any VexPro mecanum wheels, but I would trust the construction of the plastic plates, because of the rigidity other plastic VexPro products (ballshifter housing, versa-wheels). I do not know about the rollers on those wheels, but if they are similar in tread to a Versa-wheel, I would be careful and monitor the tread wear on your mecanum rollers. Damaged and missing tread will cause your robot to "hobble" as it bounces every time the wheel reaches the missing spot. Remember, a mecanum wheel is not a circle, it is a N-gon. With a missing vertex, irregularities occur. This will make actions such as strafing behave a little weird.