For no real water spots, you`d need something that sheets. I don`t think any product like that has actually made it mainstream. I think Meg`s said NXT was supposed to do that but IMO it just wore out really fast as it beaded at first.
I gave up on true coatings, just ordered a gallon of DG105 and in Accumulator style plan to use it for the next two decades and top with TW SnS which I also bought a case of.
As long as you stay away from sprinklers and wash regularly, no product should cause water spots that can`t be washed off.