Really guys a military spec lower is a military spec lower please stop the madness

If we get technical none of those lowers are actually MILSPEC.  They must be built to certain technical specifications in order to function correctly with other parts and all of those lowers are meant to meet similar design spec and I am not talking about materials used or finish.  Now this is where issues can arise from manufacturer to manufacturer. 

Day to day set up can be different and production runs can vary slightly.  Finish can also vary.  As an example a certain manufacturer may fail a part in inspection and reject a batch and then it may be sold to a different maker with lover QC standards.  Now this is not just lowers but applies to many parts.

Ever wonder why some uppers and lowers fit tight and other combos are loose?  Or why certain pins or parts kits fit and may or may not function the same with the same reliability?  Sure a lot of stuff with slap together and run, but there are reasons why certain builders have better results across the board with their rifles. 

Now can I build a reliable rifle that functions well with whatever parts?  Sure, but there is a reason that so many diyers have issues.  Poor choice in parts combos plus lack of knowledge in assembly can cause a lot of frustration.  On the plus side there is much better production these days, but to say that it boils down to whatever rollmark is not accurate either.

How about National Match lowers? 

I get what your saying but I like shiny things so when the Noveske Chainsaws Gen 1(blems) were 130 at KGS I got 2 a while back. 

I got a chainsaw for $100 from OGC years ago.
Lowers are certainly cheaper now.