Thin Walled Speakers -Tonian, Musical Affairs, etc

Hello,
It seems that a few speaker makers are using the thin walled, lightweight, less damping approach to building. For example Tonian, Musical Affairs and some others.

http://tonianlabs.com/
http://musicalaffairs.com/
http://vimeo.com/28295029

And I've read some very positive reviews of such speakers. I can see how they would sound unreal with vocals, acoustic instruments etc. But how do they sound with other more spectrally complex music- lets say rock. Do they turn to sonic mud?

I'd be curious to hear feedback from anyone who actually owns or has heard such speakers.

Thanks