IsoAcoustics Iso-Puck vs. Iso-Puck Mini

If the two models are spring based the reason why there are two models is that the spring rate (springiness) of the springs must be matched to a range of loads to achieve the degree of isolation desired as well as lateral stability. I would expect no difference in overall sound.

I suggest you consider Herbie's Audio Labs products. I use them under my 115lb speakers, amp and streamer dac....I'm very satisfied. I had used the cork-rubber sandwich squares under my Vons for years and recently switched to the small glider feet. I was not expecting anything but the bass got a little more defined and the soundstage improved side to side.