Deciding not to replace the engine in my Ninja after it played a quick game of Destroy Yourself, I have a shiny new '05 YZF600R sitting in the driveway!
For the type of riding I do (High speed "Touring"), I find the 600R handles everything I have to throw at it. After making some adjustments to the levers and bars itís very comfortable for both long and short trips.
I was concerned at what I might be sacrificing in power, but after taking some runs with friends on their Zx-7's I find that it's not much of a concern. The 600R pulls smooth and strong all the way up, so while I may get left behind some in the straights I can make up for it by buzzing through the turns and accelerating up to speed quicker.
Pro's: Nice comfy seat (important to me these days, as well as when riding 2-up with the wife). Handles well, and even though itís a heavier bike, I feel more confident on it. At 6'2" and 200ish, I don't feel like a pretzel when riding and I can push the bike around in ways that left me feeling uneasy on lighter bikes. Since this bike will never see the track, race readiness isn't a concern.
Con's: Older technology (but a bit of a plus since parts are dirt cheap as they have been around longer), and Analog instrumentation (more from an aesthetic angle).
Overall I am happy with the bike, and having put 1500 kms on it it's starting to shape up very well. For daily commuting and weekend rips through the routes it is holding up very well, and will keep me smiling for the next couple of years.
Have a couple of pictures of it, I do like the looks. Has a more "classic" sportbike look compared to the anorexic look of the modern sportbikes. Nice to have it broken in for SBW as well!
Ride safe out there, fear the cell phone wielding SUV's.