I picked up a 650mm one (Redwolf) just because it was the retardedly longest that I could find. I must admit that the weight of the tube made me worried at first. Compared to the brass tight bore barrels I am used to, this coated aluminum? one seemed very fragile. After installation I was duly impressed with the fitting and qaulity of the barrel. I find that the coating is something quite unique and seems to be better scratch resistance then the normal brass tightbores. The workmanship is flawless and to boot, it is a sexy black. I would recommend these Madbull barrels completely too!