No contest.
The stainless 67 will be easier to take care of and show less wear. If you mar the finish, scotch brite pads and maybe a little metal polish will fix/touch up most "oops's"
The blue 15 has a more "classic" look, but will show wear, particularly if it gets carried a lot.
Some of us find a well worn blue revolver to have a certain charm though.
EDIT TO ADD: I personally find nothing offensive about "honest wear" on a blue revolver.
The stainless 67 will be easier to take care of and show less wear. If you mar the finish, scotch brite pads and maybe a little metal polish will fix/touch up most "oops's"
The blue 15 has a more "classic" look, but will show wear, particularly if it gets carried a lot.
Some of us find a well worn blue revolver to have a certain charm though.
EDIT TO ADD: I personally find nothing offensive about "honest wear" on a blue revolver.