i prefer weapon shield, break free CLP is decent stuff too. I generally shy away from rem oil, not enough rust protection for me. if you want a decent lubricant with EXCELENT rust prevention check out EEZOX.. as long as you take care of and regularly clean your guns it should be an issue with anything including regular motor oil
On a side not, i really like to put a VERY light coating of high quality grease on my 1911 rails vs oil, it seems to be a lot slicker and run smoother, but that's personal preaferance.