Hello everyone, this is my first post on this site.
I carry a Para Ordnance P14.45 (like you could'nt figure that out by my screen name), have owned it for about five years now.
As for steel cased ammo hurting the gun, we all have to remember that when the .45ACP came out, all of the military practice ammo was steel case to save on brass for the war.
I have personally shot well over 1000 rnds of Wolf steel .45's with no problems, but I have to say that here recently they changed from a brown colored case to a light gray and have had some feeding problems I believe from the case not being slick enough so to speak. I have eliminated that problem by wiping each round with a very and I mean a very lightly oiled cloth and now have no problems with this case change.
When I get serious about shooting I switch to what I carry, which is 230 gr Winchester SXT.