Was looking at Aspen as a tow vehicle. I noticed the 5.7 hemi with 3.92 rear axle ratio can pull 8700 but the 3.55 can only pull 7200. Does the gear ratio really make that big of a difference.
Power wise, you have about 10% more wheel torque which really helps that (IMHO crappy) geared trans. That will be noticeable when towing, probalby not otherwise.
Neither one really matters for RVing. You run out payload and receiver limit well under 7k loaded. If you are considering towing near 7k pounds, I recommend something with more capability, payload specifically.