Like many I have used different weapons lubricants for my weapons Tri-Flow, Rem Oil and Break Free CLP among others. The one I have settled on is Break Free CLP after I did some testing last year when it was very cold and a bit this year because low temperature performance is very important to me. The stories of GI's in Korea having to wizz on their frozen rifles to get them working has always been something that hits home living cold temps and having to use a torch to get locks and other metal objects working in low temps. What I did for three weeks at the coldest point last year most of the days below zero left 2 AR's a Garand Glock and 1911 in the back my unheated truck with no special initial preparation just took them from storage for a week and then out to the the range three times over a three week period with no cleaning until after I was done. With a total of about 500 rounds through the five weapons no failures at all and no sign of sluggish cycling. There are dozens of synthetic oil formulations out there and many favorites which are all probably good and a matter of personal choice but I have settled on Break Free CLP I used it before Safariland bought the brand and will continue to use it.