I think the ZX12 horn is something to be concerned about, too.
The Busa horn is tinny, squeaky and buzzy, inspiring about as much respect as the backup beeper on a UPS step van.
If the Zx12 turns out to have a more manly horn than my Busa, I'm going over to my Freightliner dealer for a set of 36" triple trumpet 240 db airhorns. I'm going rip off the windscreen and mount the horn array on the tank.
This way, I can continue to get the kind of respect on the street that my Busa has enjoyed since April...no matter how fast the ZX12 runs.