Oh, I love the hell out of the short stroke system. I use an ESSB with a short stroke buffer system (3 stage), and it's fantastic. What I didn't have success with was the magnetic system.I like the Taccom short stroke system, cuts the stroke down to 2" and reduces recoil/movement substantially, but still plain blowback, I use a 10oz KVP buffer and 308 spring with mine.
TBH, if the MPX works out well enough, I may just buy a second one and call it a day.