It all depends where you live. If I lived in a colder climate, I'd be using the pink stuff. Here in Texas, I bypass/drain/uncork the water heater, blow the lines out with the air compressor, pump cheap vodka in and through the lines, blow them out again, then call it done, perhaps pouring some soapy water on the toilet valve.
The cheap vodka will work a little bit as a germicide and in low points, it will reduce the freezing temperature enough so the day or two it does stay cold, the water won't freeze solidly. As for it damaging valve seats, most pink stuff has ethanol in it anyway.
