re: Another building an AR-15 thread

I think the allure of owning an AR is that most are pretty interchangeable across brands. I don't know of any problems with different brand upper and lower.

As far as quality of bolt carriers and barrels, I know rock river makes a pretty good upper, and then you have colt. These are still nice uppers without breaking the bank, but I wouldn't say they are head and shoulders better than some of the cheaper ones. I have an essential arms rifle that was built last year, and it has done just fine for what I use it for.