I saw these were in stock and was wondering if anyone has shot them? Thoughts?

I assume these were designed for competition use, but if they work, they'd be a lot of fun on the range regardless
Magpul PMAG 21

Haven't shot the PMAG21s yet but have a couple of their 17 rounders.  They work fine but I like ETS' mags better.   For competition use I don't like not having witness holes to see if I've got more than 10 or 11 (or less) in a magazine for USPSA production and IDPA.  I actually carry a 22 round ETS "competition" mag as my backup mag now instead of the stock size 17 rounder for my G17.  

The MAGPULs work fine and haven't failed on me in use so far just the witness hole gripe for me.

I have 1 on order and should be here in a few days.  I expect it to work fine since I have some of the G17 Pmags and they work just fine.  

I'll run it through some drills and such when I get it.

Well, my PMag 21 came in today.  Just playing around with it, I like it.  Not too long.  I am going to try and get to the range this weekend, if I do, I'll put a bunch of rounds through it using my G34 adn G19 to try it out.

**EDIT*  Also, just FYI - It has witness holes at 10 - 15 - and 21 rounds