I rarely read the side of my gun, to be honest.
I was pretty much just thinking from the point of view of legal issues. I guess I'm thinking, "Go Multi" - because in some hypothetical legal world, that might...maybe...make it easier...That's probably the same world where I need NODs.
Ive built up rifles using Aero, MegaArms (billet), Stag and BCM lowers. The ONLY issue I have run into is my WOA upper does NOT like the Aero lower. You have to pretty much take a hammer to get the rear pin through (I dont, just saying you would) The rest work well together, so I'm going to go with a tolerance stack between the WOA upper and Aero lower.
Does the marking matter if it is an SBR?
-Seconds Count. Misses Don't-
No. Even the "pistol" marking on some lowers is wholly irrelevant to the Form 1 process.
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Not another dime.
Aero Precision has had the best fit and finish IME, but there really isn't a difference in standard forged 7075 lowers. Well maybe the occasional purple anodized Bushmaster lowers back in the day.
I've looked at Aero Precision, and found many little machining details were just much nicer on the Mega forged receivers. Like chamfers and bevels that would fall under the "fit and finish" as far as the design details go. Not to mention the anodizing appearing not right on the APs, because I already did that earlier in the thread. In total, it was enough for me to decide that the Mega lowers were a no brainer at $35 higher cost. Never looked back.
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Not another dime.