my problem with asian military mags is the feed lips: they're not tight enough.
during a tactical reload, it doesn't hit hard enough to release the slide (because it's a lighter metal than the factory ones) and the top round goes flying out the ejection port or ends up standing straight up, still in the mag, pointing out the ejection port.
if I could bend them in a little bit more, I'd love 'em. however, I don't have good tools to do that with (just my leatherman and other household-type ones), so I don't plan on using them.
maybe I'll trade them 2:1 for factory hi-caps at a gunshow or something.