I have a two seat XP 900 so your experience may differ. I run 8psi up front and 6.5psi in the rear. Smooth buff fronts, STU paddles in the rear. Sidewalls were mentioned so I will add that beadlocks on sand tires are definitely the way to go if funds allow.
And probably most importantly in this whole discussion since you mentioned passengers, stress to them the importance of keeping their hands and arms inside the vehicle, especially during a rollover. Either grasp the harness or white knuckle the oh sh*t bar provided for the passengers. Your hands are your money makers, keep them safe.