Stag Receivers are very good. I have a couple that I built and the upper and lower matches perfectly. The only thing you really have to look out for are the barrels. What ever brand receiver it has make sure it has a Chrome lined barrel. They will last you a long time and will take a lot of abuse. Other than that go for the price and the looks! Take it from someone that has built over 200 AR's, most in the 80's, lower receivers just have different brand names with some having a small cosmetic change on the outside.