If I have a choice, I always go stainless. In this Oklahoma humidity, blued steel even rusts inside an air-conditioned house if you do not keep it oiled up.
To me, whatever works best and is the longest lasting wins out over looks, so I see no advantage to blued steel.
I always thought that the durability and less likely rust developing on stainless was a good quality. In the heat of the summer I always sweat and have to keep them oiled and wiped down.
As others have said, blued is more subject to corrosion and finish wear. Either will work, given that you are willing to provide the level of care they require. Stainless just require less maintenance.
Guess I'll go with stainless. It's only about $5 per magazine in difference, which isn't too bad compared to the price of other magazines out there. Thanks guys!