I only have the PCR but haven't had any problems with the Mec Gar mags. They seem well made from metal and the springs seem as stiff as the one that came with the orig mag. I bought mine a little over a year ago.
I bought some mec gar mags for my PCR. I think they are the same mag except for no printing on one side of the factory mag.
My factory mags had witness holes and numbers next to witness holes to indicate number of rounds. Nothing on other side of factory mags.
Mec gar mag also had witness holes and numbers on same side of mag as factory. But on other side of mec gar mag was printing indicating what gun it was for and word "mec gar."
Otherwise mags exactly alike as far as I could tell. Down to every little dimple, bend, shade of bluing, etc both inside and out. Yes I disassembed and compared the inside of both mags. Follower, spring, baseplate, baseplate insert all looked exactly the same with same finish and were interchangable.
I also emailed mec gar and they informed me that CZ factory mag springs work in mec gar mags.
In short I think mec gar provides CZ with same mags they sell under the mec gar name, but without the markings on the one side.
