I've got no complaints for commuting 6 days a week.
Awesome fun for weekend rides, great brakes, confidence inspiring handling, very stable.... Smooooooooth
As Rob said they don't have as much poke down low as the 636 and the 09 10, the latter being due to weight reduction and engine modifications.
It's not a question of 'not a good roadbike' as they are a phenomenally good bike, it's just that when ridden in comparison to other bikes there is something not quite as good in relative terms.
It depends what you're happy with and want from your bike.
Reviews and Discussion say the 09/10 tramples the 05/06/07/08 on most counts, and the 05/06 and 07/08 have advantages and disadvantages over each other. Test rides time!
