Here is a response that I received from Gates about the CDX drive.
We currently have a tandem set up in the CDC line. *The new CenterTrack system for tandem is in design and testing phase. *We are hoping to have it to market by Summer 2012. *We do not have a cost for the system yet. *It should only be slightly more than the current system at $210. *The weight of the entire system is several pounds lighter than your chain system. *I do not have an exact weight with me but will get one soon.