I've been doing a little reading AFTER I went and bought some Mobil 1 for my new AR build. Oops. It seems I bought 5W20. Cane suggests 0W-30 and I've read that 20W50 is good, too. No word on 5W-20. First, what are people's experience with this as an overall gun oil? May I use it as a gun oil replacement for every location on any firearm that I would apply gun oil like Hoppe's? Or only in certain locations? Second, is the # of the oil important enough that I should go and exchange it for another viscosity? Ounce for ounce, this option has got to be pennies on the dollar compared to Hoppe's or RemOil. Thanks for the suggestion, Cane!