First, thanks for the steel color, which I just noticed for the first time. I'd go for it if I were buying now, but I'm still happy with the all-black that I've had for some months now.
I've travelled with it several times -- most recently on a mixed vacation/business trip to France and Austria. In the airport, I generally have a rolling valise and the Buzz.
I really wish there were some way to perch the Buzz on top of the rolly thingy and have it not fall off. For instance, a briefcase kind of bag often has handles wide enough to slip over the extended handle of the rolly thingy.
I have to say that I can't think of exactly how you could supply an attaching strap, but I would surely welcome it. Maybe if you figure it out and add it, I'll buy another one -- in steel. :-)