August Guns & Ammo has an interesting article "The Eternal Tradeoff" written about the quirks of ultra compact guns.
Although Rohrbaugh is not mentioned, the point of the article affirms what I have learned about us wanting +P ammo useage for our R9s. Tom Watson has made the point best, for me, on this forum and during a phone conversation.
While the article may cause angst in those intent upon being able to use +P ammo in the R9, the article advises that useage of +P would be wasted on so small a gun.
+P issue is off the table for me.