I've had 4 different bikes out on the track. So far my '16 S1000RR has been my favorite.
I will say I have not ridden any other modern sport bikes on the track so I'm a bit biased.
I'm sure all the top bikes including the newest gen of R1 are stellar on the track.
Comfort wise it's the '02/'03 hands down. I've had three of them. Love them!
I will own another one. The modern bikes are much too cramped for hours in the saddle. Especially if the roads aren't all curves.