Bill....Fran has tested the battery power feature on the BA330 ...and believe me its the real deal....and can give you unbelievable time on one set of batteries as stated by Roland....I always use the Ac adapter ...but its a nice option when needed.
http://www.youtube.com/watch?v=pvhrtt3WrFM&feature=related

PS....don't kid yourself there is some really talented musicians down in the subways making a very nice days pay .....
I retired from the NYC Transit Authority 15 years ago I know it all too well..



[This message has been edited by Dnj (edited 08-13-2010).]