Tvad, that's a really good question! And the answer is a little complicated because every TT is different. So first I'll say what I did with my Goldmund Studietto. It comes with (would you believe) four different strength springs which are to be installed (in three locations) according to whether you are using their linear arm or a pivoting type. So it was easy for me to replace them with Pandathumb Audio's "Pandafeet" in two different durometers (they make three, and they're all the same physical size)) which approximate the spring resistances in terms of relative load-carrying ability.
I don't think this is terribly critical. I guess if I were to do it with a different TT, I'd first put the lowest durometer (squishiest) pucks everywhere, and replace the one (or two) that compressed more, with harder one(s).
FYI, I tried the AQ hemispheres first. They were OK, but the Pandafeet were much better, due to the fact (according to Gary at Pandathumb) that they are uniform in diameter from top to bottom. Go to:
http://www.pandathumbaudio.com/
PS They're good under preamps and CDT/CDPs too.
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