Although (according to Kazaa) it can be influenced by your rating (if more people dl off you, then in theory you should get faster speeds), I suspect that the biggest obstacle to fast speeds is a combination of your connection and (mainly) the connections you are downloading from. Obviously you can't do much about the latter. If you are using Kazaa and not the "Lite" version, you may want to consider switching - no spyware on the Lite version, and you are set as "master" all the time. It also includes a download manager that can be set to search for the fastest available dl source.