Link below to a recent project with my sp10 mkII.
http://www.theanalogdept.com/user510_sp10_mkii.htm
I had already tried a high mass approach with stacked layers of baltic birch multi-ply. Then the idea occurred to me that 'what if' one tried a lighter but rigid platform. Wouldn't spurious energy transfer into and around the lighter plinth somewhat quicker than with the previous massive plinth. That was part of the plan.
Also in use is a Minus-K BM1-150. I already had this one prior to the SP10 mkII project. I had ordered the heavy Minus-k model to accommodate some massive slate that was under a TD124.
-Steve