Well I always thought the bad thing about this was if one piston seized up or didn't move all that great that your pads would quickly start wearing very fast on the side that still moved easily. Trying to equalize the applied pressure from 4 different small pistons can never work as good as just having 1 large one. Plus there's 4 seals that can go bad instead of just 1. BTW those calipers are exactly like mine, came off of a 72 Valiant.
Also, see the little metal tabs that keep the pads held down??? I lost mine when I had everything apart and couldn't for the life of me find anywhere that had them for sale. Until I came across the fact that they were the same calipers as that found on 67 or 68 mustangs and I was instantly able to find them for sale. Once again the dreaded "no A-body parts syndrome". Mustangs, oh yeah we've got 16 billion of those, A-Body nope.