Isolation disc for speaker spikes on wood floors.

Just did a little search, and it goes from pretty reasonable to quite expensive. Isoclean prices them as sets of 4, while others like Black Diamond and Symposium each. The BDR's are $30 each, but I need 8, so these things aren't cheap. The Isoclean's are $160/4, so they would run over $300. My sources are Music Direct, and Acoustic Sounds so far.
Palasr - intrigued by the viablue spikes. Wonder how well they would work over Herbie's gliders, which I am happy with mostly due to their maneuverability. Good looking spikes - any further comments, tips, etc on their application/installation?
I have tried many many of these under my Tannoy speakers, ranging from the typical 5 cent coins all the way to expensive Harmonix footers. The best value for money and most effective turned out to be the "Linn Skeet". You can find it on ebay UK. Produced by Linn with real engineering behind it, not just typical tone control stuff that other tweak-accessories companies sell. Try it, you will thank yourself for saving a lot of time, effort and money. Costs only GBP 50.

I have nothing really more to say about them, aside from the fact that they work well under my speakers, having gone through many different materials, spikes, discs, etc (Herbie's decoupling gliders being one of them - I knew within a minute that they weren't what I was looking for). As with all accessories of this nature, your results may vary.
I went w/ the Herbies Audio Labs. I bought 4 of his giant decouplers for under my rack. Then 8 of his DB neutralizer squares, which I will try between speakers and stands.