I had air bags on my last 3 trucks but this time I am going to go with Roadmaster Active Suspension.
With up to 40% over load I shouldn't get any squat.
I've been waiting for a friend with an almost exact same truck but a 21 Malibu to install his so I can compare. The more and more I research on this system though the more and more I like it.
http://www.activesuspension.com/