Don't have any experience with the Crossfire system but here's a link to Michelin's RV tires and their weight/pressure recommendations.
RV tire brochure
When I first bought my coach I had 100psi in each tire and just about lost the fillings in my teeth. Had the coach weighed, could only get weight per axle. Based on that my XRVs were recommended at 80 front and 90 rear (duals). Really improved the ride. Wear patterns are uniform. No excessive heat in tires on the hottest days. Minimal pressure rise when warm. Working for me.