Use alternate controller on EVT 4000e?

So its clear my controller is fried. $530 for a new one. ouch. What do folks think about trying this one:
http://www.ebikecontroller.com/motorcontrollers222346-electricbikecontroller.htm
Its only $100. may not be waterproof so I'd have to fit it under the seat, but there should be room. any thoughts?
-joe