I ride a Bandit 600S.
The two-fitty was a real nice machine. I'd actually like to have one for just tootiin' around, but I'd probably never use it.
It was very different (for me) riding the Bandit. It's WAY taller, it has more power, it handles much better (I guess . . . never really got that GZ up above 30 or so, as I remember), and everything is harder to pull (brakes, clutch). Also, the GZ would rev up like a muscle car (long rev . . . hung around before dying out), whereas the Bandit has a quick, snappy rev (quickly revs to redline, then dies off just as quickly). This must mean that the GZ had more crankshaft/piston mass (and thus, momentum) than the Bandit has.
[EDIT: Read that last sentence, keeping in mind that the GZ has a single-cylinder, 250cc engine, and the Bandit has a four-cylinder, 600cc engine. I must be wrong. Can that single 250cc-displacement piston and its rod weigh more than four 150cc-displacement pistons and their rods? It just can't be.
. . . and . . . if the Bandit does, in fact, have more rotating crank mass . . . how do you account for the revving differences? Valve train? Bearings? Lupus? Is it lupus?
Maybe I haven't put enough thought into this . . . or maybe I'm thinking too much, what do I know?