"Well Im not sure what other peoples problems are ,but these things are great. I read the negative reviews before buying them and I was skeptical at first, but ordered anyway. I wanted twin mags, ones that wouldn't interfear with my bi-pod and were cheap. I own a 30 round mag by thermold already and it worked great. When these showed up I put them together and slapped them in my Bushmaster. Fit great look great. I even tried to twist them apart and slammed the crap out of them with no failure. Now I don't leave my mags loaded for a long time so I cant comment on the other person, but I do know that even leaving steel magazines loaded for a long time can be bad for the mag. spring. I hope this review helps."
"The bullets have slipped out the top of this magazine numerous times due to the thin plastic walls. Several times while just loading them and several times while loading the magazine into the magazine chamber, leaving me no option but to clear the loose bullet out of the chamber area, releasing the magazine and reloading it."