Interesting... all of the speakers have excellent qualities, but are soooo different. If you like the glorious but limited sound of the Quads, but want the transparency of the Merlin's, with the speed of the Talon's, the beauty of the ProAcs, and some of the dynamics of the Avantgarde's, I might suggest a speaker that has a combination of all of the above... the Piegas.
I was quite impressed with them. They do everything so well and are very easy to drive. They like solid state amplification as well as tubes. They give you the best of the ribbon speakers along with the dynamics and bass of the box speakers.
I would highly suggest you add them to your short list. There are not a lot of people who have heard them, but I could put you in touch with a few other people that have replaced much more expensive speakers with them. You may look at the "Golden Ear" issue of T.A.S. where Jonathan Valin touted them so highly.
I was quite impressed with them. They do everything so well and are very easy to drive. They like solid state amplification as well as tubes. They give you the best of the ribbon speakers along with the dynamics and bass of the box speakers.
I would highly suggest you add them to your short list. There are not a lot of people who have heard them, but I could put you in touch with a few other people that have replaced much more expensive speakers with them. You may look at the "Golden Ear" issue of T.A.S. where Jonathan Valin touted them so highly.