Other advantages of MPS:
1-Doesn't elevate the Chlorine level, which means you can swim almost immediately afterward, without bleaching your suit.
2-Saves energy and cuts evaporation and Chlorine use, as you can put your solar cover on immediately afterward, without having its life shortened by high chlorine.
3-No effect on PH (at least that I can see) or calcium.
4-No bleached or faded liners or bathing suits, or white spots on clothing from splashed bleach.
5-No premixing needed (unlike cal-hypo)
6-Instant water sparkle when company is coming!