I like riding full suspensions, and i hear its hard to install a SS on those frames. I dont like hard tails, and where i ride gears are needed. even a third chain ring is needed unless you want to spin out or only go 27 mph downhill.
My brother has a SS bianchi and its light as hell and looks good.. i couldn't imagine not having gears though... i use them all the time, even in 2 feet of snow.