FA service is quality. The slickside upper is supposedly from DPMS. I bought one for a retro build. It is a rich, matte black- not Colt gray. Machining is a bit spotty in some places (like the inside of the carry handle and the charging handle channel is on the tight side of tolerance) but I find it endearing as the military has seen rifles in similar shape. My only gripe about the machining affecting function is the ramp cut for the ejection port cover detent is not machined deep enough. I have to take something thin and poke the detent to close the down. I can fix that with a rat tail file.
The barrel went in awfully tight, which I like. The A1 rear sight assy went in awfully tight too, which I didn't like.
I'm satisfied but I recognize that the upper's machining can be improved. Nothing I can't fix on my own, however.