Quad 989/2905 all around qualities

I have missed this specific Extrema by the matters of hours :-)
Somebody bought it :-) I was almost ready with the money :-)
In cash :-) Sad story, but the life goes one :-)

As for "cold" electornic music, i don't listen to it myself very often, but i have a few disks and i take always one with me to test the speaker. It reveals certain abilities (or disabilities) of the speaker. With the extrema the only problem i had was it "warm" or let's say "acoustic" type of sound.
It was perfect with all the rest, but for "cold" electronic music it was a bit
too warm for me, but again - it is a very sensitive speaker. It is of course depends on the cables, electronic equipment and alike. But i've heard the potential with in that speaker... As for its speed, dynamics and bass - i had no problem with trances or anything else... Many sais it is SF best speaker.
Never heard Amati or Stradivari (far above my room space and budget, even second handed). Mementos are of more specific-music-type oriented speakers than Extrema IMHO. Also, living with ESL63, my current equipment simply not good/strong enough to drive the Extrema...
It was my other concern... I'm using moderate powered tube amplifier with ESLs.

Till recently i was not into HI-FI/Hi-END equipment business.
I like the music, much less the equipment, but you need some level of equipment to enjoy the soul within the music... I am still learning...

Given your desire for some serious volume, i would take Extrema over memento. Keep looking...you'll find one.

As for warm on Extrema with electronic...what electronics did you hear with the Extrema?

I suspect if you'd been using a good preamp and Krell FPB monoblocks, you'd have hard superbly powerful, clean natural but not overly warm sound with your deep electronic music...

Yesterday, i have listened to Mistral Audio (see separate thread) and was impressed with it sound given its price. It is some Chinese-UK company.
It is presented in US by NAPA acoustic (I am not from the States as you may understand from my english mistakes). I don't know much of this company and it doesn't have any serious reviews on the net, but again, i was pretty impressed with the sound. It is not SF of course. Not in the build quality (it is just average) and not with that sort of multi-flavour sound, but it still was pretty decent. Have you ever heard of Mistral ?

Hi...i have not heard mistral.

did you check the Sonus Faber for sale section here? there is a pair of Amati Homages for $9995. That is a superb price. The seller is an SF dealer, so hopefully you are buying safely. The bass is way better than esl63, and for the money hard to beat in the overall sound spectrum. at least email them and let them know you may be interested...give you some time to consider your next move!