With Black coated blades, a Titaniam bsaed finish will hold up very well. Black T (Walter Birdsong) and similar high quality finishes will scuff and wear with hard usage (stripping wire, lots of hard wood whittling and,other similar things) but, with normal usalge will be very close to factory new for a very long time. The Cheaper "Teflon" finishes and various black coatings used on cheap knives will not hold up well at all.
Last time I checked, Walter Birdsong was still accepting single knife coating requests. There are probably several custom knife makers who could recoat your blade in call guard as well.
Best coating? A Ti-Nitride variation.
Second Best? Black T types finishes as seen on Emersons and Benchmades.
I have an Emerson Commander in Black T that is holding up very well. I strip wire with it and cut things like aluminum cans with it. The edges of aluminum cans have put a few light surface scratches in the blade that would probably come out if I did a little blade maintanence. The black blade looks really cool, the wave opening really impresses people (and it works very well) and, the CM154 blade holds up well to a lot of usuage.
Stay Sharp,
Sid
