Update: I wanted to make sure the new surrounds were well broken in and any caps reforming in the crossovers complete so after a month or so of side by side listening the CS3008's will be my keepers over the Kappa 6.1's. It was a close race with both sounding very similar in the high and low ends of the spectrum. It was the Crescendo's mid and mid-bass fullness that won me over.
With both using the same Kappa emit tweeters of course they were very similar, almost identical in the top end. Both were crisp and clear through the mid-ranges but the Kappas just didn't fill the room quite like the 4-way 3008's. I still love that Polydome though, it's quite a sweet sounding mid. The bass from the 3008's was a little fuller too, with it's 10" woofer and large rear port, but not much over the front ported Kappas. Both suffer from what I have come to call "busy bass reverberations". That is, while listening to jazz or Steely Dan or similarly crisp and not busy content the bass is nice and tight. When listening to rock or other music with rapidly repeating low notes both pairs tend to muddy up with a kind of reverberation that I've described in posts above. At low to medium volume it's not as much an issue. I've experimented with various amps, receivers, and EQ's with the same results. To some this could be construed as normal but to my ears it's not. I guess this confirms me as decidedly preferring the quick and clean bass associated with acoustic suspension speakers. Room acoustics can be ruled out as well because my big Kefs, AR 52s', and even Infinity Qb's don't sound that way to me positioned similarly.
I can't keep both pairs so the Kappa 6.1's will be moved along. I probably will feel differently when I score a set of Kappa's a little higher up the food chain or one of the non-ported models. It's been fun. Next up is to sideline these pairs and A/B the Qb's and the pair of RSb's I haven't given enough listening time to.