[4 of 5 Stars!]This is the second CMMG upper that I have acquired. I decided to stay with this brand, as my 5.56 version has yet to fail me. The machine work is good, the finish is done well and they are reliable. Top quality materials are used all around, and the thing that I love about both of my CMMG uppers is that they both came with one piece gas rings! They don't even list it as a feature. It may be a small thing, but not having to check the timing on the rings is very nice. Though the barrel on this 300 AAC is not chrome lined, the bolt carrier is (inside where the bolt goes. It doesn't have a fully chromed bcg). Mine also had the "T" marks stamped in the picatinny rail. Yes, there were very slight marks on the barrel from the front sight being worked into place (on the 300 AAC that I am reviewing), but this isn't a show piece.
I only gave it four stars because it is not the mind blowing, top notch fit and finish of a match grade item and the reciever's finish was a flatter black than my Double Star lower. Neither of which have anyhing to do with function and the finish is still nice. I will note that the 5.56 version I have is a dead match in finish to my lower, so it may have just been this run of recievers. In the end, bang for the buck, you can't go wrong. Flaws and all, I would say that these uppers are still worth more than what you are paying. Thank you Buds for the great price, awesome customer service and fast shipping!