I handled one in person, yesterday. I am not an AR expert by any stretch so you should take my opinion as that of a guy who is used to guns and machines but has no special knowledge of this model.
I thought that the overal machining on the thing was pretty rough. Some of the parts this probably doesn't matter on - the safety selector for instance looked like it was cast out of play-doh but that probably would not interfere with the function. I was told that I was looking at a rough example and I believe that to be true. However, I was not impressed even though people like MikeK who know more than me and whose opinion I respect say it performs.
If your interest is having an AR that works even if it's pretty ugly up close I suspect you will have no complaints. If MikeK says it runs I believe it will run.
Personally it was just a little too rough for me, and in combination with the sudden arrivement of a bunch of cheap 7.62x39 I decided to buy a CZ858 instead.
Part of this for me is that I don't intend to own a bunch of ARs, just one or two, one being for the GF. So for me, I'd be buying my one AR at $900 and then be unable to take it to the US for any classes or anything.
If Marstar brought them it at $700 I would have bought one, but although I can appreciate the arguments for this gun at $900 I just couldn't quite persuade myself.
I will wait and buy something I can take to the US instead, or if Marstar gets them in noticeably cheaper I might get one then.
But that is just me and I am not knocking people who chose differently. I can understand both sides of this equation for sure.