I always push the pistons in very slowly to keep contaminates from getting pushed back up the lines. I never had a issue with sticking calipers on any of my modern stuff with the exception of a PT that the right front brake seized up. It was right after I put on some new ceramic pads. It must of had something to due with pushing the piston back for the install of the new pads. I ended up replacing the rotors, pads and calipers, and bleed the brakes to start fresh.