Ok , her is the low down.
There used to be a FFL/type II that went under the name Sendra. He produced complete rifles and receivers and parts. The company renamed it's self Nesdra( just a respelling of sendra) then went out of business. The fathers two son's started their own companies, since they had their fathers connections on parts, but did not become FFLs.
One of the companies is Model 1, the other is M&A sales. Both produce kits, and for the most part are not bad for the price. But on the kits, a lot of parts are made by commercial manufactures, not military manufactures.
I have kits from both, one being a flat top, and for the price I paid, It shoots just fine.
If your looking for a tack driver, this upper will not be it. Also, your front sight tower is cast, not forged. But if your looking for a upper that you can burn up,or just blast with, you have found the ticked.