Dunno about the Yamaha but one of my friends has a sexy red Kawi 650R and it's a beauty. I rode it for a couple of min and also was a passenger on it... awesomeness.
The guy that I brought my 250 from also has a Kawi 650R and all he did was compliment the bike.
That would make it 3 good opinions for the Kawi in one post!!