At the moment I am looking at the Razer Orochi,Razer Mamba and Microsoft Sidewinder X8. Basically I want both ultra-smooth and dpi switchable on the mouse itself. The Orochi can use the native bluetooth for connection and is smaller, the Mamba takes up a USB slot with its own transmitter but might be better for bigger hands. The Microsoft Sidewinder x8 also looks very nice and uses its one USB toggle but is Mac compatible. The logitech bluetooth mice do not appear to be Mac compatible. Anyone who has any of the above or any others, comments gratefully appreciated!