I have been researching this for a while now...

So far, besides Airock Suspensions (mostly Jeep stuff),
I've found a decent rear air system that is available for the trooper. (keeps stock springs in place)
And, another site that actually lists an application for the VX!!!!!!!
When aired down (5 PSI) there is no change in stock handleing (according to the manufacture) and you can air them up to 80-100PSI!!! AND they can be independently ajustable! So on a steep side hill situation, you could "air-up" the low side and get through easier.
With the onboard compressor they offer, you could have the whole setup controlled from inside the cockpit

For the front, a set of Monroe or Gabriel Hi-jackers air shocks could be set up to work independtly of each other, or cross-linked for much better articulation...Dual air shocks per wheel would give more controll and more lift...

In stock form, the VX has soft rear springs, and way more down-travel than up-travel front and rear...this allows the an air suspension to work well in the rear because of the preload the spring is under.

And because you can raise the ride height and still have enough down-travel left to keep the ride comfortable

I plan on getting both and then modifying the mounts with spacers to get more lift....I will let everyone know how it goes...

Here are some links to there sites:

http://www.airliftcompany.com
http://www.ride-rite.com


Allan