The passive unit I just bought cost about $250 to air freight from the West Coast to the East Coast. Rather expensive. Kinetic Systems is in Boston and Sounds of Silence is in NH so that is certainly a more economical option if one can find one used.
I do find the filling and releasing of air manually takes a bit of getting used to. The process took about 10 minutes for me to set up initially, and it is holding level 24 hours later. The three feet are each about 1/8" over the edge of my top shelf on my Zoethecus rack, so I am looking for a large slab of granite to put under the unit to distribute the load directly over the vertical legs of the rack. The added weight at the top of the rack is not good as you can imagine the pendulum effect.
I also started looking into pre-loading options and am getting prices for 24" X 20" slabs of granite, marble and steel of various thicknesses. I hope to have a slab in the 100-125 lb range to play with pre-loading.
Vibraplane does make a newer type device which only weighs 45 lbs, has a smaller footprint and seems to be more user friendly. I've never seen one used, but there is an excellent review in Positive Feedback.
Dan, my passive unit can be filled up with a compressed air tank/canister. This may be easier than the hand pump, but it still will not have the automatic self leveling feature, which could be very convenient.
