It depends on who you ask. There are guys who claim that they've shot an army's worth of steel-cased ammo through their rifle and probably just as many who say that a box of Wolf ammo ruined the extractor on their carbine.
I'm not a metallurgist and the only steel-cased ammo I shoot is out of an SKS, so don't take my word as anything remotely like the gospel, but one opinion that I've heard several times is that if the extractor groove on the case isn't cut deep enough, the steel cases are really hard on an M1 carbine's extractor.
That's about the sum-total of my experience, though.
Well we don't rent pigs and I figure it's better to say it right out front because a man that does like to rent pigs is... he's hard to stop - Gus McCrae