Independet Suspension - Air Bags vs. Suspension Block

There is also the Timbrens Axle-less independent suspension system. Seems like a pretty interesting proposition with no air system to maintain. Kind of a similar approach as Mor-ryde takes with the rubber spring. However, I like the fact that the spring is directly over the arm. They also offer a 4" lift suspension as well on there. Don't have any experience with it, but it'd be interesting to see if anybody on here does. Just throwing this out there.