It's been a while, but I've heard the 50s at length (although they were passive and driven by Linn amps fyi) and they are very impressive for what they do -- I'd expect the active versions to be even moreso. There's a level of dynamic power, directness, and clarity in the midrange in particular that is quite unlike anything else I've heard from other speakers. Not sure they do the audiophile trickery (i.e. dimensional soundstaging, etc.) as well as some others, but if you're into real, honest, dynamically powerful sound reproduction in my opinion they're a must hear -- for future reference if nothing else. Hope that helps a little.
