I've built several ar's. Nothing high end. The first ones were surplus ammo and arms . I believe they were made by Aero. Built a few Aero , several Andersons , Range Tool , Palmetto , Mag Tech magnesium. The most recent was a KE arms. I seem to wanting to try different manufacturers just to compare them. I've had good luck with all of them. The lettering on the one from range tool was pretty bad. Looked like they used a dremel. The KE arms anodizing is a little different. I thought it was duracoat at first. Anyone else buy lower's just to try something different? If so any noticeable differences?

I don't have any Mag Tech and never heard of KE, but have used all of the others you mentioned, along with a couple Tapcos and a Spike's, and have had nothing but good results. My RT lowers are blank ones except for their manufacture info, and they are really nice looking lowers.

The PSA, LMT, and BCM lowers I've had are not appreciably different except the markings on the PSA seem to be a bit sloppy. The BCM seems the most refined.

I have several anderson, lancer, mega, aero, and had one off-brand Liberty a while back.

The anderson and liberty were not great, they had thin coatings, very light color "black", tight pin holes, some interference fits that should have cleared, etc. No problems, but a few things that weren't quite as nice.

The mega and lancer have excellent deep and very dark colorer coatings, excellent lettering, no machine marks at all, and installation went a lot easier.

The aero was in-between, with a good finish, but still tight pins.

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