They're mostly as good as the components they use, and both use fairly decent stuff. I like the simpler design of the Windtrax system which only has one pump - I've seen it done both ways and the color change is only 2-3 seconds when you mix the colors between the tanks and the pumps. IDGAF about instant changeover in the bays. I took a close look at a D&S system for the first time a few days ago, and they actually have four lines to each bay, with three pumps and four banks of solenoids PLUS one on the side of three of the banks to control the color change, then there's four separate tube lines to each bay.
I don't really like either system because the tanks aren't enclosed. At least the Windtrax ones have a partial lid. FWIW I used to build equipment, and we always had the Hydrominder fully enclosed in the tank. I've made tanks out of 6" PVC where there wasn't room for anything else, and I would mount the Hydrominder to the cap and drill holes just big enough for the discharge tube and chain to pass through.
