The fact that this is a special edition, would account for the higher cost. You now need to ask yourself a few questions, that only you can answer.
Do I have the extra money to spend for a special edition firearm. (Remember, this particular gun could really jump in value at some later date.)
Is the blued stainless of any real value to you. If this gun will be used for hunting, the combination of a dark finish (less likely to spook game) and stainless steel (a little more forgiving in damp or wet conditions) might be worth a few extra bucks.
How many are being made with this particular finish, and will this become a standard finish for S&W in the future. (If only a few are being made it has greater potential for becoming a collectable. If it might become a standard finish, the future value might be less.)
In my opinion, if this gun were a .44 mag. I’d jump on it. Since I don’t hunt with a .357, I would not spend the extra money unless I wanted the gun as a collectable.