Don, for barrel recommendations.. cookie was right Bar-Sto is considered best by many. Others include Jarvis, KKM, Lone Wolf Distributors, and Storm Lake. All of them are good and have more chamber support so that one can safely shoot reloads if they wish. Although, even the barrel manufacturers say it will void their warranty, etc. ... as a saftey precaution. I do have a couple of Lone Wolf Glock barrels. They seem good and are drop in (Bar-Sto mostly drop in.. some have to be gunsmith fitting because of their tight tolerences). LWD barrels are more accurate that stock. But, not like light and day. But, they are cheaper too.. so??? Hope that info helps.