Funny you ask, the dual bag rear system for the short bed Dodge Ram 3/4 ton was actually designed on my truck a few months ago and has recently become available, see their web site for more info at keldermanmfg.com and if you go to the truck air ride page my truck is the top right one. .
The front air ride system will definately help the ride, although the front does not ride too bad due to all the weight in the front, the front bags are usually installed for people using snow plows, etc. in order to keep there front end from sagging, the rear system is where you get the nice ride from, since the rear springs are so stiff and there is no weight in the back you usually get the hard bumps and jolts pretty severely depending on the road you are on, this is hard on your truck and usually shakes some bolts and other things loose in time. I am running the system that has the air pressure adjustment in the cab so i can add and remove air as needed for load, i currently run around 20-25 pounds for a nice level ride. It rellay smooths out the ride and you can watch the rear tire in your mirror as you go down the highway and watch it bounce up and down and the air pressure gauge needle also bounces up and down but you hardly feel the bumps because the bags are taking most of the punishment. I actually gave a friend of mine at work a ride and he could tell the difference in 200 feet ! and he was the 2nd truck to have it installed, he hauls his antique tractors to tractor pulls and says his wife will actually go with him now because the truck rides so much nicer. .
Also if you haven't noticed i may be a little prejudice because i am a Kelderman also and my uncle owns the place but i swear by them, i get calls from him every now and then to give people test rides, if you go to the web site you can watch some air ride videos that actually show the system working under the truck as it drives down the road... ... Barry