IMO and many others the answer to your question is NO. If you want to know why just Google "gun show reloads".
BTW, if you want to blow up an AR15 like a small nuclear explosion all you have to do is make the mistake of using 24 grains of a fast handgun powder such as Titegroup instead of a much slower powder such as CFE223. Now suppose your reloader has a bad habit of keeping multiple bottles of powder on his reloading bench. In addition suppose your reloader enjoys a beer or three while he is reloading. So, do you really want to purchase reloads at a gun show from someone operating out of a basement or garage? If you want cheap ammo for target shooting just look for Wolf Gold at that gun show. It probably won't cost any more than those reloads and it's a commercially produced ammunition made in a factory with real quality control personel.