I have the Eagle Cap 1165 on an F450. It's heavy. The dry weight is 5,000 but I weighed in at almost 7,500 lbs. with a full tank of water. I'm not sure how I have that much stuff in my rig so I plan to weigh it again soon. It's way too heavy for a SRW even with 19.5" wheels.
I had the Dodge SRW with an Eagle Cap 950 and stock wheels. It handled terrible.
I went to the 19.5", Rancho shocks, and extended bump stops which handled very well. I had this setup for 7 years and was very happy.
Then I went to the stock F450 DRW with the EC 950 which handled slightly better.
Then I went to the EC1165 on the F450 which handles worse than the EC950 SRW with 19.5"s.
I already added Energy Suspension Bump Stops and added leaves to the spring pack. It is much improved with the added leaves on the spring pack. The F450 has plenty of power to still accelerates up step hills with the camper, but I still need to do some mods to improve the handling. My next mods are going to be Bilstein shocks and a Hellwig rear sway bar. Maybe 19.5" wheels some day...
I'm very jealous of people getting the 2014 F450 stock with 19.5" wheels.
On a side note to anyone getting one of these big rigs. Don't bother with airbags. I used my airbags for straight highway driving (lifting off the overload spring) and leveling at camp with my EC950. The EC1165 is too heavy and doesn't budge the camper off the overload springs.