Most “disappeared” speakers.

Egglestonworks Emma Evolution is a great speaker. Vandersteen Treo will blow you away. Martin Logan ESL-9 is quite spectacular. I am a dealer for these. The most important person is you. It's your money, couch and taste...Happy listening.

If you'll consider used think about Thiel ,
read the Thiel Owners thread ( over 6,000 ) and see how much praise they receive from the owners , myself included .

My Reference 3A MM de Capos. Sweet!

From all the speakers that I have heard it is usually the monitor speakers that do the disappearing act best. The less MDF to rattle around the less the speakers reveal themselves. I like the Chapman speakers sound good, they are transmission line speakers and the usually cabinet rattling bass rear waves have an escape route that seem less obvious then sealed or ported. 

My most wide soundstage speakers were the old Bose 901s. Distance from wall and more importantly wall material are critical however. I had an apartment with brick wall (3 deep) separation and the sound was magnificent. Moved to a house with drywall and I couldn't sell them fast enough. My message: Room is everything. Good luck!