Anybody have experience with both versions of this pedal? I have the 9.6 volt version, and it is one of the best chorus stompboxes for bass that I have ever found. I have read a few posts where people implied that the 18 volt version is superior. Is it true, or do I just have pedal envy? How hard is it to find the 18 volt power supplies? I know where I can get the 18 volt pedal, if it is better, but it doesn't have a power supply.