Jim,
Just my thoughts about Breakfree and RemOil. I think they're very similar. Both have teflon additive suspended in a light oil. I only switched to RemOil because it was cheaper and more convenient in small aerosol cans and it wasn't quite as odiferous in the house.

With regard to greases, I don't see how any of us could say a superduper expensive grease would make any better wear difference on a light duty application like a gun when compared to your choice.