S4RS....no doubt, if you can swing the $$$$. Just bought one and after 35 years of riding and racing bikes, this is some hot machine. Full ohlins around and radial Brembo's make an outstanding machine. Motor is simply purrrfekt and garantees long grins for many years.
Got a pearl white one (lucked out since hard to come by) and bike is simply "sexy".
Only the Italians can design machinery that beautiful and that racy.
S4RS is my vote