I’ve used Herbie’s (Tender Feet, Big Fat Dots, Spike Decoupling Gliders for speakers), all to great effect. I tried IsoAcoustics Oreas under my amp and other components and returned them. I’ve now tried Townshend Pods under my Tambaqui DAC and now under my new Makua Preamp (with embedded Tambaqui) and I think they are the best. That said, I’m not convinced yet that they are the best for all of my components.
I find each have their own impact on tonal balance. Herbie’s tamp down upper mids a bit while creating a pleasing highly rhythmic and deep bass and opened up the soundstage while unlocking upper frequencies. IsoAcoustics Oreas boosted the overall sense of scale and “bigness” under my Gryphon amp, also opening the soundstage and improving upper frequency clarity, but they sounded overblown and overdone on my system - too “big”. Also they boosted upper bass in an unnatural and bloated manner. Townshend Pods under my Makua (and before that my Tambaqui) was more even-handed, but MAY have slightly boosted upper mids a bit. But clarity is improved, soundstage depth improved, bass is tighter, and I think the impact on tonal balance may be the most even-handed of them all. They make the sound less “dark” with a more free flowing sense in the upper mids and high frequencies.
Of course this is in my system. I’ve ordered a couple of platforms for my Gryphon Amp and Makua preamp. Based on my experiences so far I feel confident this is a good choice for the Makua. Not sure about the amp yet. And not sure about the Pods (vs Herbie’s) for my other lighter components. Once the platforms arrive I can experiment moving the Townshend Pods under my other components. It’s hard to do that now as I lose the benefit of the Pods under the Makua when I do the switch. I’m not convinced at present that I will prefer the Pods to Herbie’s on the other components but we’ll see.
One thing, I think the highest value is with Herbie’s and at least from my experiences in my system would far prefer them over more expensive IsoAcoustics products. If you are on a tighter budget I think Herbie’s is a no-brainer, and for me the jury is still out on whether I prefer Herbie’s to Townshend for SOME of my components. So far I know Townshend is the winner under my preamp/DAC.