I would also go with the stainless steel, it matches with everything and always looks nice. I especially like the stainless in the warmer weather since it won't stick to skin.
I much prefer SS! You can get it wet without worrying.. and it lasts much longer than a leather band (I have owned both). Leather bands tend to stain at the area where you clasp it and take on the shape of the wrist.. just not as attractive as SS. Just my opinion!!