I've been lucky and have been able to own a few different bikes thus far. What i expect from a motorcycle is pretty simple: dead reliable in all conditions, comfortable and versatile.
All of the motorcycles i have owned have met these conditions in varying degrees and some even added some extra to the mix. So far, out of all the bikes i have owned, the FZ6 seems to be the best blend of them all. I know that many people here have the FZ6 as their first or near first bike, i will give some observations of my past bikes (all had more cc's than the FZ6), some things others might want to take into account when they are eager to ditch the "tiny" 600 for a liter bike.
-83 Honda CB650SC
Good: cheap, reliable, cheap, got decent gas mileage, cheap, easy to learn on, cheap
Bad: it was getting worn out, the brakes sucked, the suspension sucked, the seat sucked
Verdict: perfect bike to learn on. It is still the only bike i ever dropped and i only dropped it once. Because it was so old and warn, if it did any damage, i didn't notice.
-'04 Honda VFR 800
Good: A dramatic step from the CB, the best headlights i have ever seen on any motorcycle, looked dead sexy
Bad: wrecked it after having it 1.5 months with 4752 miles, i ran it into a ditch because i was stupid and wasn't trained to ride that bike. I learned so much from that crash.
Verdict: Awesome bike that i didn't deserve. It paid the price for my stupidity.
-'04 Honda VFR 800 (had to replace it with another!)
Good: Smooth, looked great, awesome luggage, V4+staintunes=audible sex
Bad: poor gas mileage (averaged 40mpg), proved to have "issues" (VTEC, surging, thermostat), heavy, fairings in the way of everything
Verdict: I used this VFR as my learning tool, what i should have done with the first bike. I gained so much confidence with this bike, rode around 15000 miles in a little over a year before i sold it.
-'02 BMW K1200RS
Good: OMG intoxicating torque, unbelievable smoothness, looked great
Bad: guzzles premium fuel like it's going out of style (39mpg is the best i got), terrible headlight, even more fairings to get off, HEAVY (weighing in at a good 650+, that's around 50% more than the FZ6!), had FD issues
Verdict: I am glad that i got the chance to ride/own it, even more glad i sold it after riding it 3k miles for a profit.
-07 FZ6
Good: economical (i average 47-49mpg, regular fuel), easy to work on, looks decent enough, light, more than quick enough for the type of riding i do, the best fueling i have had on any motorcycle.
Bad: needs a more powerful stator, needs ABS
Verdict: This bike is trying its best to do all i need and is making it. I have many mods planned for it over the next few months in an effort to make it a perfect bike for me and unlike any other FZ6 around.