I think it is soo worth it. I mean, you can buy a set of used aluminum heads for 7-900 on ebay but they are usually used and beat on so you have to take them ( I would take them anyways) to a machine shop and that is going to add to the cost as well. I will say that I am very interested in the aluminum heads from PAW. Anyone have anymore information on them??? decent amount of flow out of the box and I wonder what they will do once ported.