DNJ - I think he meant 'Garage Band' software, not that he plays in one.

GARY - the extra pedal (there's a socket for sustain and one for expression) can be used on certain SA sounds to add additional expression:

Guitar - body slap (which gets really old really fast) or on some, it allows a switch to guitar harmonics.
Sax - taking a breath (which is totally useless)
Trumpet - falls up or down
And a few others - some useful, some gimicky, but overall, a nice feature.

Tim