I have the 2607, and I looked at upsizing the wheels last year. Didn't think that there was enough clearance between the tires or between the tires and the wheel-well.
Instead of going to the 15" Maxxi's that I wanted to, I ended up purchasing the 14" Kumho's. The Kumho's gave me the load and speed ratings that I was looking for. One season on them, and I really like the ride.
2014 RAM 2500 Laramie 4x4 Quad Cab w/Cummins Turbo Diesel, 2009 Rockwood 2607, and 3 'yaks!
300W of Suntech Solar, a Rogue MPT-3024 Controller, and a Xantrex PW2000 Inverter