We've really only driven it around the hallway a few times, just to see if everything fits and works as planned. There is still no shifting hardware, but everything else is there.
On the middle wheels, we are noticing some notable peeling on the rubber itself, only from maybe 15 minutes of usage, on a smooth concrete-like surface. Also, these wheels like to pickup everything and anything on the concrete that we run it on. We have yet to do any heavy testing such as being pushed sideways or anything. We also have yet to run it on carpeted surfaces.
At any rate, we shall see what these wheels stand up to. I personally love the fact that we have finally built a robot that actually rolls smoothly
Also, the centers of the wheels are machined so the holes are enlarged, and we simply have spacers and bearings riding on an axle on the corners, and a hub for the centres driving the other four wheels. Thus, we are not concerned of stripping the drive configurations that the wheels are shipped with because we dont directly apply power to the center of the wheels.