Wow, I had the opposite impression!
I've heard the S5 right after the Q7, with the same setup (Soulution), and the S5 impressed me more than the Q7 (in relative terms, of course). Also heard the Q3 in the same setup, but on a different day so couldn't put them side by side...
It seemed a bit wider than the Q3, but not as deep, as the Q3 is "boxy".
The S5 plays louder, with more punch, and the trade off is indeed a little less refinement.
I guess it'll depend on ancilliary electronics and what kind of music you hear. For rock and jazz, the S5 was amazing for its price.
alexandre
It looks like we agree more than we disagree. I heard the Q3s with Lamm and the S5s with Constellation.