As far as the alloy is concerned, who has noticed any problem with this so far? The Sport II is probably the best low end AR you can get. Never an issue with mine, and accurate as all get out, even though all its ever been fed is the cheapest brass cased stuff I can find. Independence or American Eagle basically. I won't stoop to steel case anymore though, but I've shot my share of it. You can blow a lot of money on a higher end AR, but think about what you intend to use it for in the end. Most of the time its bragging rights that you own some $$$ AR. Most put a dang 4MOA dot on them and at that point, its how well you can shoot with it more so than how well the gun itself can shoot. Myself included. If you are doing some precision shooting with a high powered scope, I can see it, but for most, they will get the same out of that Sport as they will something more pricey. My brother in law's M&P TS has never shot as good as my cousin's Sport or my Sport II. Who even knows why, but that gun has been a problem child.