Steel case ammo is made for a softer form of steel,but it is still harder than brass. The main problem associated with steel case commie ammo is it's just more dirty and harder on the shell extractors of some pistol and rifles but not all. Some firearms fire thousands of rds. and never have a problem while other wear and brake extractor easy.
When fired the steel case doesn't expand in the chamber and seal it as tightly as the brass case will thus letting some of the gas blow by the case neck and shoulder and carbonr residue will buildup in the chamber,then when you switch to say brass case ammo without cleaning in between the brass swells in the chamber tighter and with the carbon residue buildup causes the case to stick in the chamber,this is most often seen in firearms that have tight chamber specifications and are not as loose as the com bloc weapons which are designed to shoot the steel case ammo.
As long as your particular firearm handles steel case ammo and doesn't cause any function or wear problems shoot it all you like,just remember to clean the weapon especially the chamber area before switching to any brass case ammo. The lacquer coating is almost a thing of the past now all the com bloc ammo mfg. are or have switched to the ploy coating. Personally I like the lacquer coating myself better than the poly,I've seen the ploy coated ammo rust in lesser conditions than the lacquer coating ever would.
The lacquer coating buildup is more of a myth than anything,the carbon buildup is more of the problem,just clean your weapon when your done with your shooting secession and you want have a problem with either. One thing to also pay close attention to with com bloc ammo is the primer sealant they use on some ammo it has a tendency to gum up the works a lot faster than the lacquer coating ever will especially in the firing pin area.
I shoot some steel case ammo in various rifles and pistols and never had a problem it's dirty but decent ammo. I wouldn't use it in a CCW weapon but for about anything else it's fine and cheap if your not a reloader.