I have airbags on my F250, and they've really helped the ride- they are more known as "load-levelers", but a side-affect is the rideability. No springs are taken out (in fact, for heavier loads, it's a good idea to add a product such as their Add-A-Leaf System), which an additional leaf. Together with the RS9000X shocks I put on, it's a pretty good ride.
The only thing to worry about in buying an existing TV with one, is "how old". The air lines are plastic (nylon), and unlike us guys, DON'T get better with age!