Blue is beautiful but when carried daily takes a beating, that wear and scratch on a blue finish will bring a tear to many.
Stainless is beautiful, but much easier to take care of, scratch removal and overall general cleaning. A more durable material for everyday carry
The warm climate owners, they all know which to carry.
And of course, some don't care about the finish at all, just want to use it for its intended purpose, protection.
I own both, but stainless is usually the one that is my traveling companion, always.