When it comes to comfort and long distance rides, it is always advisable to go for a cruiser bike. Out of all these, the best one would be the Yamaha R3 as it's aerodynamic fairing along with an upright riding position can help in covering more kilometers on a single stretch. The Benelli Tornado 302, BMW G310R are still to be tested on Indian roads while teh R3 is selling in desired numbers currently.
KTM RC390 does not feel stressed at 100 kmph above speeds but its aggressive riding position and heating issue can cause comfort problems on highways for long rides.