The Mr. Clean product works okay but is poorly constructed. Water leaks out of the bottom of the unit when you use the filtered water and the 'no bucket' method is horrible. Where am I supposed to put my wash pad and wheel brushes? The soap is nothing to write home about either. The RainX self dry product is probably the biggest piece of garbage I've ever bought. Half the time, the soap wouldn't dispense and whatever that rinse polymer was supposed to do to eliminate spots, it didn't do it. Real fun with a black Excursion.
Anyway, the type of product I envision being the best would be a combination filter/sprayer and you'd use traditional car wash soap (like NXT or Gold Class) and a bucket and the filter/sprayer would be used to spray down the car, rinse the soap off, the switch to filtered water for the final rinse.
How about it?