The wash is nice, but I don't like that there are only two mitters. The second mitter, I know the sides are short due to the small rocker-panels, but the mitter looks like it got a hair cut and not super effective. It also seemed kinda dark at the dryer section. However, I like the high pressure they got.
Amazing video!
Finally
Edit: Also the z wrap mitter combo is probably the most convenient kind of combo. It would be very effective for a mini tunnel to use.