Saw and handled this toy about a month ago... the one that I handled had shoulders that wouldn't lock into position. I asked the owner if there was a way for the shoulders to lock in and he said no - they just sit there. It's a nuisance because the shoulders dislodge every time you move them, which makes it a minor irritant when posing and a
significant frustration during play!
Now I don't know if it was just this one toy or if this is a common problem. Please let me know if other people's MPM OPs have this issue or not... don't leave me in the lurch thinking it's a common issue like I did with MP Lambor!

But just to ensure that I don't fall into making that mistake again, I will disclaim that I have only ever seen/handled
one figure. Awaiting confirmation from others to see if this is common or if my friend just lucked out by getting one with loose-as-goose shoulders. Much like the shoulders on my old MP Lambor, they stay in position just fine if you don't touch them or move them veeery carefully/gently, but they're otherwise highly prone to coming out even with moderate force. And for a post MP Lambor toy you'd think that they'd include some basic way for the shoulders to lock in, even something as simple as a tab (like the way that MP28 Hot Rod's shoulders tab onto the body - it does the job well enough).