Isolation footers for amps

I'm looking for advice/recommendations for isolation footers for my amp -- an Audio Research D300 (solid state). Currently I have it mounted on a free-standing 4" thick maple block, with spiked-tipped brass footers anchoring the base to the carpet on top of a basement (cement) floor. Would I obtain any additional sonic benefits by placing after-market isolation devices between the amp and the maple stand? I should add here that I'm not looking to spend a great deal of money on this... something more in the range of $100-200. Options in roughly that range I've found on line include Audio Prism Isobearings, Herbie's Tender Footers, and Mapleshape's brass footers. My (perhaps imperfect) understanding is that the first two are meant to isolate a component from vibrations in the room (including those from other components), while the third is supposed to help 'drain" vibrations from the component in question itself, thereby minimizing their transference to the audio chain..

I'd welcome advice from fellow Audiogoners more experienced than I on the extent to which these devices confer audible sonic improvements and, if so, which ones they'd recommend. Thanks

Michael