Dillinger- From what I see in your posts you seem to be in pretty good at a shop. I don't know if you are aware but Brownells has discounts for FFL holders and armorers. The retail on the magpuls from them is $14.95, with the discount they are $12.97. You may not like them as much as I do, but I can bet you won't be disappointed with them. Even being polymer, they are more "solid" feeling than the aluminum and when you see the feed lips, you'll notice they are very well formed and strong as opposed to the aluminum ones that are just bent to "close enough". If I had one complaint it would be the way they fit in my Cav Arms lower, a little wiggle but still feeds perfectly. I understand the Cav lower mag well is cut to a different countour to accept .45 ACP mags for Olympic's .45 upper so I am sure this is part of the reason they fit a little loose. They lock in place fine, they can just be moved about 1/8" or so side to side, but not fore and aft. They fit very well in my Stag, DPMS and Essential lowers. I also like them for a strange reason: when in a hurry or in the dark and trying to find the mag well by feel they don't ding the hell outta the lower. Also the bodies don't get gouged up to leave nicks inside the mag well/ lower. I sometimes don't have time to check all my mags during training during load ups so this makes me happy too. I Good luck.
"People live too long, dogs don't live long enough" - FTF Member-