I have a soma rush as well, and it's a great, fun ride - admittedly, it's a bit like the kilo at a much higher cost. The kilo is a great frame and if you like it, you should keep it. There is no need to upgrade for the sake of upgrading. When you have the full budget for an aluminum track bike test it out at the LBS. The Trek T1 is a nice light bike that many recommend and can give you a good feel for aluminum without the FTP/Concept price.