Back when Russian steel case ammo was much cheaper, I bought a lot of them. I've fired 7,000 rounds
of Russian steel case ammo in 9mm (i.e., TulAmmo and Barnaul) in my G43 without any issue.
There was not perceivable damage or excessive wear on any part (e.g., barrel, extractor) when examined through a x30 magnifying loupe. Despite the popular misconception about the "steel case" ammo, the "steel" used for the case is very soft and thus it does not wear or break Glock's OEM extractor. So, based on my direct experience, I can attest that shooting several thousand rounds of it will not harm your Glock.
That being said, Russian steel case ammo in 9mm is relatively low quality, weak and dirty. It barely cycles your Glock but makes your Glock very dirty, so you would have to clean it more often.
Today, if it is no longer substantially cheaper than other "range/practice" FMJ ammo, I see no reason for using it...