In my neck of the woods I have never seen a MPA. Not even at any gun shows. I would think at the prices advertised every Gunshop would have them on their shelves.
When getting into bull sessions with guys about pocket carry, the names that come up are Ruger, Kel-Tec, Taurus, and Seecamp at times, and rarely Rohrbaugh. I figure only a few hardcore guys may know what a MPA is, if any at all.
Just makes me wonder if there is a supply issue or manufacturing problem.