Thanks to those with useful comments.
I’d like to say that not everyone needs to hear the “does it shoot reliably” speech. If we have have looked here, and read comments, and learned here, then we (well, I, for sure) already know that. However, I’m sure you can’t know that because you don’t know me. No harm, no foul.
There are, on occasions, other, additional questions in play in a post of this nature. For example, in this case, if the initial rough machining is also an indicator that potentially the rails (rails? the bearing surfaces on the BC) are out of spec, then that would be a good visual clue for me. Do I know that? No. Do master armorers here know that? Probably. Hence, my initial questions. Perhaps I should have been more explicit.
Also, where the forward assist notches are cut INTO the rail (rail?), the bolt carrier is literally sharp enough to cut into whatever gets in its way. Should I care about this? Maybe, maybe not.
Is the machining on this part equivalent to that on a Colt? BCM? LMT? I don’t know, I don’t have those to compare with. According to pictures I have seen, I believe the QC on this part is of a lower standard than Colt, BCM, LMT, and DD. Believe, yes. Know? No.
And no, my feelings are not hurt (for the crowd who are thinking that). I tend to me more of the “engineer in the corner” with my questions.
The manufacturer has responded to my inquiry with a request for more information, which I have provided. I anticipate an amicable outcome for all. I’ll post an update when it’s all finalized.