Eventide Stompboxes will work with any Expression Pedal that is a simple resistive load (potentiometer) with a max value of 20kOhms. We've successfully used the Roland EV-5 (set the trim pot to 0), the Line6, and the Boss FV-500L (connect with a stereo cable).
As for power, currently we only recommend using the power supply that comes with the stompbox. However, Voodoo Labs is working on a new version of their Pedal Power that will be compatible with Eventide Stompboxes.
Alan
