Pneupod NP-1 Pneumatic Isolation Feet - Feedback please

I still have a bunch of the Townshend Seismic Sinks, both the original version made in the UK with adjustable feet, and the U.S.-made non-adjustable version. I liked them better than the Bright Star (which I also used to have), they being made of metal rather than the BS's MDF. Having each foot individually adjustable seems like a great idea.

The foot looks very good. Townshend Audio takes a different approach to providing isolation, using a spring inside a bellows-type semi-sealed container. You can see a video demonstrating the Seismic Pod’s effectiveness on You Tube. It sells for around $500 for a set of four.