Having used AP calipers with a removable top bridge, and PFC calipers with a fixed bridge, I've been able to swap hot brakes (calipers and pads; yes, you need gloves but that's the case with either type of caliper
) in the paddock in the same amount of time - I wouldn't put a heavy "weighting factor" on how pads are installed in a caliper when selecting a brake setup.
JAJ's statement about pad compound availability for a given caliper is definitely more important than how the pad is actually installed. Given the calipers you are considering, the choice of pad compound/material will make a bigger difference in brake feel/pedal firmness, initial bite, release characteristics, modulation, etc, than the caliper itself - yes, there will be advantages/disadvantages of each caliper but finding the "right" pad for your driving/braking style will make the biggest difference! I don't think you'll be disappointed with either brake setup; however, it might take time, and money, to find your favorite pad(s).