Thanks for the response. Is there any way I can determine the amp stability at sub one ohm?
On a similar note, I went to the California Audio Show today and listened to the latest Quads on the market, being driven by an absurd 100w CAT amp. I wasn't all that impressed though that's not to say quads aren't great. Just didn't like this particular set up (at all) and the music they were playing was tedious. One of the residents of the Quad room explained that Quads (across the line/over the years) are easy to drive (he does with an Air Tight ATC1 which he didn't bring). 30 watts vs 5 watts is a lot however.
All that being said, I spent the end of my day listening to a pair of King Sound electrostats which were simply nuts. If I had the cash I'd seriously consider a pair. Best speakers at the show (for me).
Back to the topic, I love my Almarro and would love if it could drive some Quad and thus am tempted to give driving the 57's (which I don't own at the moment) a shot. I'll report back if I do.