Audio Research...

This is like trying to guess in advance what a future buyer might prefer. You should choose the finish that makes you happy and assume that the ARC will too.

If I cast a vote for one or the other, I choose black, only because everything else in my system is finished in black and tends to "disappear" in the bookshelf or rack.

I've owned several ARC pieces and have gone back and forth over which is better. The silver is the more 'classic' audio research look, but the black does indeed seem to fit into modern decore a little more. Black is easier to touch up in case of scratches. Seems that resale is not really an issue with either color. The one constant has been that I always have mismatched components ! At one point I had a ph-3 titanium finish, a silver vt100, and a black ref 1 !

You can get faceplates from ARC for all major components.
They are quite expensive. A cheaper option is to wait for one to go for sale on audiogon, or put up a 'trade' ad.
John.

It seems to me that the natural silver is more popular or more available. Just a hunch.