I won a 30 rnd CMMG mag a few weeks ago and man I likey!!!! It's coated inside and out so the internals slide freely and quietly, like buttah! It has a stainless steel anti-tip follower, that doesn't tip at all, and a special bi-metal wound spring that you can leave a loaded magazine and it won't take a "set". Overall with a price of 29-30 bucks a mag, they are well worth the money. You can buy the spring and follower to upgrade your existing mags, $14-16, and will let you all know how they work when I get a set for some old mil mags. Best part of this mag was, it was free!!!!