Unless your some superstar motocross racer guy you will never tell or feel a diffrence in the power or weight between aluminum and steel. Ironman sprockets are garunteed to never wear drop 100 bucks on one and be done with it Sidewinders are excellent as well... Also i changed gearing mid season and my 45t sprocket was perfectly fine after running 2 diffrent chains on it and the new chain was never affected before or after the swap.. same with the front i changed it out as well a few trips later just trying new combo's.. Not one issue.. Ill gladly replace 2 or 3 steel sprockets vs buying one of those overpriced hunks of aluminum IE renthall that will wear in one or 2 weekends of riding. Again its a matter of opinion only. Steel works for me.