Honestly, the whole "which is the correct A2 stock" issue has bugged me for quite some time, because I most certainly want the correct "MIL-SPEC" M16A2 stock, but unlike some of the more highly publicized specifications out there, A2 stocks are just "not that cool," and therefore there's not a whole lot of information on them out there versus commercial knock-off versions.
For that reason, with A2 stocks, though I may end up paying a little bit more, at this point, I pretty much just stick with factory Colt or Colt take-off A2 stocks. It seems like the simplest and easiest way to "make sure" that you get the correct stock.
That being said - surprisingly to me perhaps, I've heard a lot of good things about DPMS' A2 stocks, and I say this not as a DPMS fanboy, I consider DPMS rifles a low-end, but serviceable entry-level commercial offering.
However, my suspicion - with nothing to back it up, mind you - is that for better or for worse - DPMS' name does in fact stand for "Defense Procurement Manufacturing Services," and they have supplied parts to the government on occasion in the past. I wouldn't be surprised based on what I've heard about DPMS A2 stocks if one of their contracts "back in the day" when their primary business was in fact Defense Procurement and Manufacturing was as a subcontractor for M16A2 stocks.
Like I said - this is all speculation, and I do not own a DPMS A2 stock - but what I've heard here and there about them along the way is that they are actually seem to meet the "MIL-SPEC" pretty well in all the ways that can be verified from a visual inspection of USGI M16A2 stocks.
~Augee