5,000 rounds in my Bushmaster AR's, never a problem whatsoever. None, nada, zip. No stuck shells, no broken parts, no wear that can be attributed to the ammo.
That metal-to-chamber myth is retarded, btw. The case is coated with polymer, and the case itself is SOFT metal. Don't believe me? Take a Wolf case and step on it...it'll crush.
If polymer Wolf hurts your chamber, then your gun is teh suck.
I wouldn't run it in a tight-chambered match gun - but for your garden variety AR or Mini or AK or pistol - it's the cherries. It stinks, it's sooty, and it's SLIGHTLY underpowered, but it's also nearly half the price of the good stuff. For range time or messing around, there's nothing better.