I totally agree with Donny's last post..

I use the laptop with every tune recorded as an MP3[usually my band material]..I also have another 8 thousand tunes for my DJing episodes on certain gigs..

I too Have the arranger[G70] for style play and real-time [left hand bass/ piano/drums] tunes..The G70 is also my back up [sequences on board and ready to go]..

I also carry my Zune..this is my complete back up, with all my MP3's organized for DJing or ready [separate play-list] to back up with the band..

You can't get a better , complete system than this..