If you get true heavy dampening shock, ride quality unloaded will suffer. I went with adjustable Rancho 9000's because of this. There was a noticeable difference in dampening between minimum and maximum settings. Unloaded, I could run 1/3 to 1/2 the dampening and get a good ride. Once loaded, I would set dampening to full and also get a quality ride.
The truck camper section of the forum is probably the most versed in shocks since they carry a lot of weigh at a high COG verses the low COG of pin or ball weight which is typically less most truck campers.