I need a 512mb Compact Flash card type I. I'd like it to be low batt consumption and pretty fast. What do you guys suggest? Would a new camera, like the Canon S400 take advantage of the fast speed cards? http://www.mydigitaldiscount.com/ca...products_id=123 I am getting confussed with this speed of the cards... Do I need something like this? Does the camera even write that fast?