Hi Mike,
>>in a small room with an emphasis on intimate accoustical type music i would think that this combo could be 'incredible'.....as David writes<<
This isn't what I meant nor what I wrote, and you also know that I judge everything playing classical music. The ML2/X1 combo plays full orchestral music in pretty decent sized rooms, at live volumes, with ease, jazz and rock is a sinch. You need to experience two pairs of ML2s and an X-1 then you'll realize what I mean by virtually unlimited power. I'm not talking theoretical here, its real power.
>>if a person can financially consider 2 pairs of ML2's, there are other speaker or amp combos that might work better than this particular one for large spaces.<<
There's nothing that can touch the ML2 on purity of sound and naturalness, you've never experienced real live bass reproduced properly until you hear the ML2s; and in combination with the X-1 you have a foundation that nothing I've heard can even begin to approach; unless you add an XS. I know you had the Watt/Puppy but they're not the X-1 and Puppies need a lot more power to play loud. There's a lot to a great high end system and playing at realistic levels is only one of them, the X-1s are phenomenal speakers sometimes given a bad rap due to bad setup and weak ancillary equipment, otherwise they have detail, speed, realism and a sound stage way ahead of most other speakers in their price point and higher. The only other speaker I know of equal quality is the JM Labs Grand Utopia, I can't comment on the Alexandria since I never heard them in a familiar environment.
I'm not sure what you mean by large spaces, one of the systems we set up was in a 35' x 60' x 13'.6" room and there was no shortage of power there. Of course one of our vintage horn systems with a pair of ML2s can play louder but that's a totally different story.