Rem Oil is definitely NOT overrated. It is a very good product. I use both Rem Oil and Breakfree CLP in the gunsmithing shop. Rem Oil is easier to use on the trigger group of a shotgun, for instance, while CLP has better cleaning properties. Beware of ATF and/or Acetone around gun finishes or particularly around polymer guns. The ATF will definitely swell some otherwise impervious plastics (like the Nylon in a Glock) and ruin them. I have a Marlin Camp 9 in the safe right now that I am having to replace the entire trigger group on because some fellow used Ed's Red (which contains both Acetone and ATF) on it.
My stand on oil is that you should use gun oil on guns and automotive products on cars.
Bolt&Barrel Gunsmithing, LLC
NRA Life Member, NRA Certified Instructor
US Army veteran