Actually, it is funny you mention it. I bought my Busa at a dealer who sells Triumph also. I told him I was primarily looking at the Busa as a sport touring bike. He suggested I would enjoy the Daytona 955i.I already have an 03 R1, so I did't think I was interested in the Daytona. I was going on a trip to Vegas from SoCal, and wanted to buy a sport touring bike. I was heavily influenced by this website:
http://www.pashnit.com/hayabusa-mods.htm
So, I bought the Busa and took it to Vegas after breaking it in.
Opinion:
1) I am 5'6" tall, so the bike can be a little unwieldy in the handling department compared to a lighter more nimble bike.
2) The bike can be ridden in what I like to think about as sportsbike mode and sport tourer mode. As a tourer, it definitely needs some accessories for comfort. As a sport bike, its probably one of the most dangerous bikes out there, but what a friggin blast if you got the skills.
3) Gas mileage sucks in Sportbike mode (high revs), but what a blast especially around 8000 rpm and a nice sound too. In sport tourer mode, it is an acceptable 35-40 mph (6th gear on the highway). The nice thing is that even in sixth gear at 80 mph, the bike still pulls, but you have to account for the lack of stopping power in sticky situations, so either stay out of them or ride in a lower gear.
4) It isnt very comfortable as a sport tourer in stock configuration. There are accessories that can ameliorate this, especially a double bubble or Laminar Lip.
5) Suspension is very comfortable as a Sport Tourer
Personally, I think that the new Triumph Sprint ST 1050 is the bike to look at today as a Sport Tourer that is more in the sportbike genre.