I got my FZ6 in March 2004 and got 7500km (4500miles)on it. I had the seat refurbished as it was hard like concrete and badly designed (to harsh on the back side). Now it is perfect. I put on givi side and top cases, blue like the bike, it looks awesome and unbelievably practical. You can leave stuff in it just like the trunk of a car.
If you do a lot of city travelling with it, you will feel quickly some pain in the wrist, and after two hours I start to have some pain in the knee area, so the ergonomics are not totally perfect. That being said, it is a motorcycle where the level of comfort is simply put in another league, compared to my previous bike (Volusia 2001).
As for power, it is more than sufficient for our roads. About the rear brake, you just don't use it, in hard braking situations it locks too easily.
Yamaha's claim for that machine is right on it, it does everything well and suit my changing mood
I definitely recommand this bike, but not to new riders, because it can surprise you.