Cutler adjustable weights are good - make sure you use loctite to hold the setscrews in them. As far as the secondary, it has been my experience that the RK Tek torsional conversion works better then the Cutler unit. They are both good setups, but the RKT unit holds RPM, and better backshift. Don't buy it off the shelf though - call Kelsey with your weight, riding style, and mods - he'll set you up with a kit that will work for you.