For years, I have been using oil on my pistols. However, Sig recommends grease, lubes their new striker and hammer pistols with grease, and has included some grease with new pistols. Bruce Gray strongly recommends grease as does Rick Holm. For the last three or four years, my wife and I have been using Lucas grease on 320 based competition pistols with excellent results. Still been using oil on my Glock and custom 2011 pistols. I asked Ed Cameron, an excellent 1911/2011 gunsmith and his recommendation is oil, as his guns are tightly fitted. He isn't particular about brand but said thinner oil in the winter and thicker in hot temps.
Thoughts?