I have a Magholder that works for my glock 19 and 26 9mm magazines. I did not like it at first especially at the 9-10 o'clock position because it prints worse than a pistol. I kept playing with it, and found that for me it works perfectly in the 12-2 o'clock position (pistol is at 3-3:30) butted up against the holster clip (iwb concealment solutions black mamba). At this position it costs me nothing in comfort, concealment, or reload speed. This is my first magazine change, the second is in a desantis pocket magazine carrier which I also highly recommend.
Have not seen any in leather, but that is an interesting thought because of the added comfort of leather on the corners.