They are elite because they explode right through the hole and when they see daylight, I think McFadden has better speed through the hole but not by much and Peterson does have better moves. I doubt we will be very high next year if we make the right moves this year so I would say Peterson over McFadden, unless the Raiders think we aren't going to do very good which in case is not very good.
If they both came out this year it might be a different story.