I got mine from an ebay supplier (huggablez) and while they do have a compatibilty chart Klipsch is not listed. However they do say this:
I saw a very interesting video clip as to why the Complys possibly limit the treble and muffle the bass. You can view it here:
It makes some very interesting points.
I found these on Amazon, which are memory foam tips, listed as "by mobeast" and they list the S4 as compatible. On the other hand, while the S4 uses Comply TX-100s, the mobeast list on Amazon also includes some Senns that Comply says fit TX-400s, so maybe they are making stuff up. The S4 stem is TINY-more like 2 mm.
Thanks for that video, the technique they show really helped! Probably will try out some Mobeasts anyway, they are only 8 bucks for all 3 sizes to try.
Edited by ender323 - 12/28/12 at 4:25pm