I vote for the isocups too. I use Symposium Rollerball Juniors as well. I think they are slighly better, but you can get about 10 sets of isocups for one set of rollerballs, no contest. I bought mine with the acrylic balls, I asked about the ebony ones and he threw in a set free. What can you say about that. I could'nt hear much difference, as Herbie suggested I would'nt. The Big fat dots under my speakers are pretty good. as for the tube dampers, I do'nt think you can find cheaper anyware.
I use 4 isocups, but I use a tube amp waying 55Kg