The King Cobra was offered in Blue, but I would say you will find 20 Stainless ones to every Blued one you find. You'll see more 6 inchers than 4 inchers, and more 4 inchers than the 2.5 snubbies.
More collectable ?
It depends on who's buying it.
Is it being purchased to be put up as a collectable ?
Then the Blue ones would be the way to go.
Are you buying it to shoot it ?
The Stainless ones will last you a lifetime with-out having to worry about the finish.
The Blue finished King Cobras were dropped years sooner than the Stainless KC's.
FYI: There's also a brushed stainless and a Ultimate Bright SS. The brushed is the most common.
Sorry about the hairy knuckles, they just grew that way.
It's a 6 incher-I'll think on this one for a bit. Just bought a 6" blued Python (haven't recieved it yet-the red tape in Canada is amazing!) Should recieve it in another couple weeks. Can't wait.