[Perfectlap]

its good and bad.

It works great if your car is CLEAN after a wash.

Bad if the car didn't come completely clean after the wash. Sometimes you can't tell right away. I used it one time, after one pass the blade was dirty. I cleaned it off and washed/clayed the car again. But how many people would do that?

If the water blade is not imaculate after doing the whole car, its trouble. Like any other detailing task you want to avoid friction and rubbing on dry surfaces with dry towels and applicators. Everything should be at least damp.

IMHO the best method for drying the car is the one that swirls the paint the least.
Most professionals I know (on their own cars) spray a quick detailer like Meguiar's or Mother's on the car when its wet (lubrication) and dry with a waffle weave towel (not microfiber). I gerally use the big bottle of quick detailer that the Clay Bar people force you to buy.