I had an older 90's vintage Mini Thirty, and while it was pretty reliable with the cheap steel cased ammo, it wasn't particularly accurate, but the gun may not have been accurate in general, I never tested it with "good" brass ammo.
I really wanted to like that Mini Thirty because it looked cool, but I had some failures that were not ammo related, and I couldn't hit anything with it, which or may not have been ammo related.
I personally wouldn't want any gun chambered in 7.62x39mm that didn't like the cheap stuff because brass cased ammo is quite steep in price. I guess if it was used for hunting, and not for plinking or target shooting, it wouldn't matter as much.
I prefer the SKS and AK platforms for 7.62 general shooting since they are not picky about ammo at all.