Hard chrome is tough to beat for the externals.
I have weapons that have been treated to the Robar NP3 version of electroless nickel(has teflon or similar lubricating plastics added in addition to the electroless nickel) on the internals of the firearm. The lubricity and life are fantastic. Robar can be run dry - without lubricant if necessary.
I have a friend who had a handgun treated with the Birdsong finish. It is susceptable to external scratches, etc. Internally it looks as good as the day he got it back from them. That was many years ago and a few thousand rounds through the weapon. Externally it does show finish scratches.
If I want good looks, charm, and personality on the exterior I would go with hard chrome. Internally, I would get the Robar NP3.