It's a good quality upper assembly--certainly worth the price. But as others have said, the MCSR handguard is fairly fat. That's for a reason, though--the tube is large enough to let some suppressors fit inside it. That, and the adjustable gas block, make it a good option if you're considering a can.
The handguard is also fairly comfortable, I should add. No sharp corners or need for rail covers. I will say, however, that I'm not a huge keymod fan. Not that they don't work, but there are limited accessories, and they tend to be expensive.
The crappy cell phone pic below shows this upper (in 16", of course) on a rifle I just gave my brother-in-law 2 weeks ago. I installed a couple short rail sections on the MCSR to give him a little more flexibility.
The rifle was certainly not "high-end" (not a Noveske or Larue or KAC), but all good quality and it ran like a champ. I adjusted the gas, sighted it in with the BUIS and the little Leupold, and handed it over. They put about 300 rds through it and had a blast. Brass landed in a neat pile about 5 ft away at 4 o'clock, and my niece (first time on anything other than a .22) was bouncing tin cans like a champ.
I did not shoot it for groups, I'm afraid, but I'd say it's probably close to an MOA gun (not sub-MOA, maybe, but certainly less than 2 MOA).