They seem to go for $550-600 on GB, but that's GB prices. If one came up for sale locally, i'd see if I could get it for $450-500, if not a tad lower.
They have a bit of a premium over the polycoat Combats, but probably only to people who are looking for that specific finish. For the average joe, they're probably not worth much more than a standard black polycoat.
I love Combats and have a '94 in Black Polycoat, a '13 in Black Poly as well, a '99 blued, and an '05 Duotone. I'd love to get a satin nickel one to complete the collection, but they seem to always get stupud expensive on GB when one pops up.