It is a supertrapp, and it sounds pretty good. Honestly, I haven't ridden the bike since early 2007 so I can't say for sure as I don't remember much and I only had the bike for a short period of time. The supertrapp was on there when I got it and I never got the chance to open it up and see how many disks are in use. It also came with a few boxes of parts that I have to sort out including another exhaust as well which I can't remember what it is.
As the weather warms up, and my garage with it, I'll be tinkering to get it back running and checking over stuff and fixing what needs fixing. I'm sure I'll crack it open and count the disks to see, might play with that and the other exhaust. I'll be sure to report my findings as I do.
That'll be an awesome birthday present for your daughter. I have a Yamaha FZ1 as well, so this'll be something for me to play with, ride to work when the FZ is down for maintenance, play on the track with and most importantly, to teach my wife to ride on. We'll see if she get's bit by the motorcycle bug.