I think you guys are looking for a fast acting, long travel Land Rover Air spring/ shock system.
I like the idea and I always wanted to see the system plugged into a high out put compressor and a resevor large enough to double for tools and tire inflation.
Having worked on Land Rovers I can tell you that this is a headache enducing system and the most commen problem to bring newer Rovers into the shop.
I think if the pump and resevor operated at higher psi with a regulator to the air bags you could run the system faster maybe oversized high flow high pressure lines could help with reaction time. Maybe electric in cabin controlable relief sylonoids to "blow off" and lower each corner indevidually... Or even lock modes.
THe LR system can maintain different heights, self adjust to center weight, raise and lower; but it is too slow acting to make a lot of dynamic use out of. It also doesn't have the kind of travel that we aspire to and nothing worth bragging about. The older LR systems just try to keep the suspension level more than keep the vehicle level. Mercadies claims a fast acting system for level cornering and braking on some of thier vehicles.
A lot of people get tired of paying to continually repair the system, leaks, sylonoids, bags and relays, etc. and choose to move to springs... If you could find sombody who is willing to sell thier system and replace the bags with something more like the smaller diameter bags from Lincoln or Caddy.
I have been entersted in this for a while and kind of wondered if you can make a cheap homebuilt system with something like this:
http://www.rcplaneguide.com/X_UFO_RC_Flying_Toy.html Use a sylonoid in place of each motor with a controlled release at each corner and be able to manually over ride the ride hight. Just some thougts. NMc