Was lucky enough have a few hours with these yesterday.
I run a pair of 8351, 1238 and W371+ 8361 at the moment and can say with confidence that these are completely different to any of these.
To me the perceived volume you get from these is beyond the 1236 and far beyond any HIFI speaker I've ever witnessed. Think a PA level sound pressure with zero distortion or artefacts on the sound. It simply beggers belief.
Bass goes super low with, again, kind of authority and detail that I've never heard before. You could feed the speakers whatever and whatever volume and no problemo whatsoever.
Midrange has a kind of elasticity and depth that sounds a bit alien at first. Everything seems a bit too deep but brain seems to catch up pretty quickly and then its just simply wonderful.
Was a bit affraid of the compression driver at first but it just works.
Basicly you have a very detailed, extra deep wall of sound that seems to do whatever you ask it to do, even at extreme sound pressures. Beyond impressed myself.