I work for a company that makes electric meters. Involved in that is the in house manufacture of metal components and electronic components, which presents entirely different sets of manufacturing challenges. Add to that the QC of quite a few outsourced plastic components, the requirement for precision placement of *all* those components (within thousandths for many of them) to get a functioning product... and that doesn't even begin to touch on all the software R&D that goes into it. The legacy stuff can retail for ~90 bucks or less. A magazine is an *extremely* simple device by comparison, yet still retails for.. what are they, 20 or 30 bucks each? They don't require that proportion of engineering know-how. Not even close. I just don't believe it.
This is one of two main reasons I did not preorder a x39 kit. With a new source for the mags, I guessed there would be a high probability of some kind of issues, and that is proving to be true. Why are they not doing final QC on 100% of these shipments, since they *know* there is a pattern of issues, and they *know* these issues are not sorted out? It really is quite amazing.
As far as using AK magazines on an XCR or other next gen rifle, that is not something that I personally have any interest in, though I can see how it would appeal to some. If you are using an AK magazine, you are essentially giving up many of the advantages the XCR has over AK's. If I wanted to shoot an AK, I would do that. Just my personal opinion... To me a SCARspec rifle needs basic features like a functioning bolt catch and reasonably fast mag changes, and if they can't get the magazine right to allow for that, I'll just save $1100 and buy an AK to start with if I just have to shoot x39. But I digress...
Hopefully they can get the magazine issues worked out. As long as there are some working examples out there, it should just be a matter of time/refining their manufacturing process.