Last year I decided to bred some of my own rats so I could have fresh pickies available for my hatchling BP's. For my initial breeding stock I choose to spend the extra money for some nice masked Russian Blues from a healthy line. I figured if I was going to go to the trouble of keeping and breeding rats I'd might as well bred interesting looking rats.
Obviously the snakes do not care if their food is a cool color or has Dumbo ears. The only thing I believe that matters with feeders is that they are healthy and not dehydrated or malnourished.