Saw an ad for this device in my local Porsche club newsletter, went to their website a few times, and finally deceided to spend the money.
WWW.crspotless.com
It's basically a big double cartridge water deionizer. Plumb a garden hose in to one side, garden hose out to hose end sprayer for rinse water. 0 TDS rinse water no water spots! at all, period. Rinse and walk away.
Really big deal for me as the only place I have to wash my cars is in the sun. Hard to get the car dry quick enough.
I figure it comes out to about 25 - 30 cents per gallon for the deionized water. But at most using a pressure washer you only use a gallon or two to rinse the car.
The cartridges are supposed to last for 300 gals. of water. I'm quoting the cost for supplies here, they have different sizes of deionizers.
I have no interest in this company (wish I did) just a satisfied customer.
Saves me a lot of time keeping the fleet clean, I love this thing.