AIM has sold several different versions of AIM-branded carrier group: economy and "premium" versions, which are distinguished by the front right side of the carrier (standard radius on economy, faceted angles on premium) which also have different gas keys, gas key screws, and extractors; and phosphate, nickel-boron, and nitride treated versions. So the answer for one version may or may not apply to another.
That said, I've been using an AIM bcg, in the economy but nickel-boron coated flavor, for about a year and 900 rds in a PSA upper. I've had no problems with it, and no function issues with the upper. 900rds isn't much but it's better than zero.
Because the deals have been so good and in the recent past BCGs were as precious as diamonds, I bought a couple others. The economy phosphate version from more than a year ago has fairly poor staking. The premium versions (I have one each nickel-boron and nitride) look to have been much better assembled, and judging from appearance only do look to be premium products. I'll probably be trying out the nitride one in the near future and will post experiences when I do.