You are not going to be able to carry anymore payload by going with the 7,500lb bags but have the potential of making your ride rougher so I would stay with the 5000lb bags. Also, I regret putting the dual channel compressor on my truck as I don't need to control each side individually and by keeping air from going side to side it makes the rear axle rock the truck more on lumpy ground. However, if you do need to control side to side for some reason dual channel could be very useful. My father liked dual channel on the truck that he used for hauling a slide in camper. It really helped when leveling the rig.
