I am getting ready to do some upgrading soon and am tying to figure out which combo to take. For the longest time I was waiting for the 1D4 to come out because of the video capability in the 1D package (which I actually care about). But after seeing the price, I'm not sure it's worth it. I shoot weddings and travel quite a bit both of which I prefer natural and available light shooting. Which combo is going to give me the best high ISO quality? They will both cost about the same amount out of pocket. So what would you do in my shoes? John