Thinking about getting a MP 9C, but i was just curious as if anyone has ever seen a base plate that has the pinky extension but is also flat so your palm is also engaged with the little pinky extension?
I have done the 14 rnd extension per the post by Raisin so I think the answer is mostly no. Here the angle is filled in but the half moon piece that is the head of the backstrap retainer and forms the rear bottom of the grip is still the same. Search for his thread for pics.
I tried the X-Grip with 17 round magazine but didn't like it because it was too big to carry. Also the 17 round mag would not always drop free when I pressed the mag release button because my palm was up against it and held it in place. So for me the Mec-Gar +2 extension for a 14 round magazine was the perfect size and the magazines do drop free because my palm didn't press against the magazine.