Which is better the boss rc 20xl or the Digitech Jamman? (The one that looks like the rc 20xl)

Also, do you need a power supply for them or can you use battery's?
and would any power supply work or would I need a specific one for them?

EDIT: I also remember hearing that the RC helps you loop where it cuts the space when you stop the guitar so when it loops it doesn't sound choppy when it re starts. does the Jamman have that?
Last edited by schism8 at Apr 28, 2011,
I know the jamman solo is betterthan the rc2 but im not sure how it all pans out once you get into the next tier of loopy goodness.
no sir away a papaya war is on