We have a Spectra watermaker and it works fine. In warm water it seems we need to clean the filters often. We have started to wash them each time we use the watermaker (about every 3rd day or so) and never if we are in a marina).
Sailingdog is correct about the effect of chlorine on the membrane, but ours is connected to our tank and we do fill it with tap water, but we have a charcoal filter (as recommended by Spectra) in the line
for the flushing water.