Blued. Never really cared for stainless. Nickel even looks better with some wear. I understand the supposed advantages of stainless, just can't enjoy them like a blued gun. A dedicated pocket gun may be worthwhile to have in stainless, or for someone living in a humid environment, but I've not been all that kind to my blued guns through many years of hard use, and they've always worked just fine. So long as a little surface rust now and then doesn't make you have a cow, blued is fine.
Like Bob, I like the honest wear that comes with use on blued guns.
"Far better it is to dare mighty things, to win glorious triumphs even though checkered by failure, than to rank with those poor spirits who neither enjoy nor suffer much because they live in the gray twilight that knows neither victory nor defeat." -Theodore Roosevelt-