I just wonder if the tolerances on the PSA nickel boron BCG are the same as a more expensive BCG?
I think some guys have gone over this, like MontanaMan. I don't know what kind of "tolerances", you are looking for and for what reasons? Better more consistent accuracy, or better reliability? I'd say if it's "milspec", it's good enough. Especially when it has a great reputation like the Toolcraft does. Like what's been said, Toolcraft makes these for many different companies. If there was an issue with their "tolerances", I think we'd know about it.
I know this is not a Toolcraft, but I've had excellent service out of it:
That's how a NIB BCG should look. When I say "NIB", I am referring to the Nickel boron coating. A well done unit, shall wear well, not flake off, and remain pretty stain free. It sounds like the Toolcraft is a great BCG, that I'd put my money on. I'd only hope it wears like this RTBA BCG has. And no, I don't know what "tolerances" that BCG has either. The rifle shoots very well, and has never had a malfunction.
Yeah, I'd put it up against a DD, or anything else. Is that the kind of "tolerances" you are looking for? I'd buy a Toolcraft, though, if I had an extra receiver to put it in. Just sold my BCM, because that one didn't really impress me much..