This pupppy is pretty powerful just running off the batteries.  We've used it on a couple of gigs an it worked well with the volume only half way up.  We are not guitar players and are not using guitars with it.  We are using an mp3 player for backup.  The sound is not quite as clear as we get with our Roland Cm-30 (so only 4 stars from me).  The micro cube is a lot easier to transport and set up and it's nice not to have to load up cart to roll around.  Guitar folk will like this unit with the fx features.