For those considering the CRSpotless system, The lifespan of the resin is determined by the water quality going in. Hooked up to my well, I can wash the boat and truck one time. Hooked up to the municipal water, I may be able to get 6 washes. Boat and truck equivalent to about 5 FGTs.
I buy the Resin in the drum for the best value, $215 shipping included. Lasts a couple years;
http://www.crspotless.com/replacement-parts/replacement-resin-drum.html
Dr. Frank. I agree, sprinklers are the worst, but even our copious amounts of rain will leave spots. Maybe Zaino is not so great?