Overall, I am extremely happy with this motorcycle. It is my first real bike, after having owned a 250cc scooter for the last 9 months. I can't say enough about the looks of the bike.
Acceleration is great, tires are nice and smooth, and no hop that others have mentioned. Great gas mileage for me so far (avg. 45mpg right now).
Only thing that kind of bothers me is the seat. I went on a 90 mile ride recently, and I noticed that when I got off the seat, my lower back was a little numb, and I could feel a slight buzz, so I know there was fatigue because of the seat. The handlebar is perfect, no leaning forward for me at 5'10". I do think the pegs are a little to far back for my liking, and would add extenders at some point.
The bike is very stable even at very low speeds. I can keep it upright without putting a foot down at 2 mph... so weight seems to be very well balanced.
The front brake is great, however the rear brake seems a little lacking, but it is a drum. The clutch itself is very easy and forgiving even for a beginner.
Exhaust is stock, with baffles still in, and it sounds great to me. Not too loud and not too quiet.
I agree with others that at 75-80mph I am looking for a 6th gear. It could really use it, as the engine does sound like it is wound pretty well.
I wouldn't really change anything about the bike, just get a different seat to my liking and add a 6th gear.