black matte on american series

[chop123]

Is the black matte finished on the american series of sbe and m2 of sub quality?Seems like a lot of people are having problems with rust.or is it the same that is on the comfort tech black matte version of sbe and m2.

[KB Fab]

I'm pretty sure those receivers are aluminum, not sure how they could rust. I'd also bet that the barrels are blued the same as the other ones. Where are "these people" you speak of that are having "problems"?