We have been running our test chassis on some sheet plastic that we think is similar to the official stuff. I'll take a close look today, and see how well the wipe test works, but our wheels have been getting a scuzzy look, kind of like what your mouse will accumulate. No idea if that helps or hurts traction, but it sure is gross!
We have about 10 hours of drive time on those wheels now, hopefully we won't have to go through more than one set before ship.
Wetzel