I have three 24"X20" Vibraplanes from SOS (Sounds of Silence). Two of the units are active (requiring a compressor) and one is passive (bicycle pump). I did try two used units found on Ebay for $350-500. THEY DID NOT WORK. I tried to use parts from both to make one functional, but in the end, it was just too frustrating. Repair estimate from Kinetic Systems was about $1,600 for each unit, so I went ahead and bought new units. The old style isolators and valves are no longer supported. The new units function perfectly.
One unit is under my 120 lb turntable and the other two units are under my SS amps. They each improved the sound, pretty dramatically. I was surprised at the improvement under my amps but was lucky to have borrowed a pair from a friend before I bought them.
I also had Steve from SOS order me from Kinetic Systems, two 135 lb steel ballast plates finished to match the VP units. These plates combined with the weight of my equipment approach the maximum design load for the units and thus they optimize the isolation.
Adding the steel ballast plates improved the performance of my components almost as much as adding the VP in the first place. These are very heavy units and extremely effective. They must be placed on a very sturdy platform, but the results and value are outstanding. They are much better than the Townshend Seismic Sinks. Details can be seen on my system page.
