Both Lance and AF have their pros and cons. So far you are well positioned with the 3500 dually as both Lance and AF campers can or more appropriately are very heavy. You may still need air bags, overload spring bumpers, sway bars, etc. Just depends on the camper you choose.
AF has a crowned roof, Lance still uses a level roof. Lance uses their Lance lock construction that minimizes stress cracking at the weld joints, AF just solves the same issue by building heavier frames. My perception between Lance and AF is that you can do pull ups in an AF by hanging on the cabinets, I would not do that in a Lance. AF campers tend to be a little heavier while Lance tends to be a little more expensive. At the end of the day it is what you want and what best deal you can make. I have so far owned three cabovers and nothing is perfect, I would gladly have either.
