I have used one on my 27gl for 1 1/2 years now, powered by a Mag5 for my return. I'm very happy with this simple switching device, just wish I was the one who invented it
A tip for cleaning, soak it in a warm vinagar bath once a year just to rid any calcium buildup, other than that I wasn't impressed with the hose fittings, so just to be safe I added a couple of hose clamps.