I think Knowshon and Aaron Curry are the only people I'd put over Sanchez and that is only because those 2 will likely be starting from Day 1 while Sanchez still has to win his job against a guy with experience.
Percy will be fun to watch but he won't be way faster than everyone on the field. He also doesn't have a quarterback that is that good at throwing the ball and he also isn't going to be the focus of the offense. I figure 600 total yards and 4 TDs sounds about right.