Mine cheerfully shoots high and low brass just fine. The only thing it doesn’t like is Winchester Universal. Then again, there are pump guns that don’t like Winchester Universal (let alone other semis) and it eats the Federal equivalent just fine so I don’t see that as a problem.
I watched videos on youtube of lots of saigas shooting low brass. I bought a nice after market gas piston and gas regulator but to no avail. I sold the weapon and made a little.