There is ALOT of second hand internetz crap talking about the steel Korean AK mags sold by Amercian Tactical.
I own two of them (30rounders). I bought them becasue they were cheap and wanted to try them out against the perfect working Chicom and Hungarian mags I already own. I picked my two randomly out of a box of 100 that were all seald in little plastic zip lock type bags at a gun show about 7-8 months ago.
I'm just one guy... but I'm one guy who actually owns these things so here is my observations.
Slightly thinner metal stamping than either the 30rnd Chicom's or my 20rnd Hungarians.... but they don't buldge out or anything when you load them. They seem very solidly made. The springs feel like they have the correct tension as compared to my others.
Fit in mag well of my Norinco NHM91 perfectly. No looser or tigher than the others.
Feed/function perfectly. A day at the range bump firing and just regular firing (couple hundred rounds in all) went fine with 0 failure to feed out of any of my mags. Ammo fired was TWC FMJ, Barnhaul JHP and some Romanina Surplus FMJ I bought back in the mid 90's. I didn't do any stupid crap like try and mono pod the rifle on the mags... why do something proven to casuse a FTF in any mag?
Personally I don't have any problems with the Korean mags. They worked out of the plastic bag they came in and were only $9.00 a piece. How they hold up over the long term I don't know but I'm looking forward to finding out.
Will