AS you can see it's mostly a matter of preference. I prefer blue in traditional style guns like single actions. However, for more logical and practical reasons consider these:
For me a holstered field gun is stainless. You won't have to worry as much about finish wear, rusting, sweaty hands, etc. And you might want to consider grips of man-made materials instead of wood.
Otherwise for me on the range or plinking, I use my blue guns.
If you can't decide, just look for the best deal, you can usually find blue guns a little cheaper. Also look at used blue guns to get an idea what they will look like after some years of use. In fact for a using gun, I always prefer a good used gun for a better price and also not having to worry about putting the 1st scratch on it.