I agree. I avoided box mag fed shotguns my entire life because I didn’t want to deal with issues. KUSA caught my attention because they’re using original Izhmash plans and specs (not a cast copy of a copy), but made by people not stumbling around from vodka.
The Csspecs mags do need to be filed to fit, which I don’t have a problem doing. I’m hoping I can get them to work, and just get a bunch of them and not have to worry about plastic durability issues.