Actually I like Nathan and think he is a superb rock singer and be perfect for the part, although it seems as though I am in the minority here!
I did not see him being big headed at all during the initial stages of the competition in actual fact he was close to tears more than once when he feared that he was going to be sent home.
To my mind the only people that have mentioned he is big headed were the judges. I wonder if this is a bit of game playing, I feel that Rory is the judges favourite, but I do not think that he looks the part or is one of the strongest singers. If they suggest that Nathan who I think is one of the best singers in the competition is big headed and over confident, the papers will probably ramp it up and before you know it, his chances are scuppered because the public start to hate him as has happened to some of those on X Factor.
I too like Roger, but feel that his voice is not quite right for a rock musical. I think that the young 21 year old (Jeff?) is very good and looks the part, but for some reason the judges don't seem to rate him so I guess that he may have a bit of an uphill struggle if he cannot win their support.