I am new to the AR world so bear with me. I watched a YouTube video and have read a few other places that all stripped lowers, stripped uppers, and LPKs are equally reliable. (Of course assuming they are all made from the same material, not a forged lower vs. a polymer.) One writer said there are only a few manufacturers of lower relievers and others just add their roll mark. Same with uppers and parts kits. This seems far fetched to me, but I figured I would see what you guys think.