Have to say that the injected 900 or 1000 would be my motor of choice - I love my 900ie and it never fails to make me smile despite it now being nearly 8! The S2R 800 however would probably be just as much fun and there are a nice few trick bits on there too...
Happy hunting for the bike of choice - I gave up a blackbird then a fireblade to come over to the side of the twin and have never looked back in nearly 10 years of owning a Ducati
