Most “disappeared” speakers.

No, you are not. You don’t come take my speakers away. Lol
Which speakers have craziest soundstaging and most disappeared image costing around $3-6k used or new, bookshelf or floorstanding.
(Need pointers, Not asking how to set them up 101.)
My $250 used and vintage Spica TC50 monitors speakers.  Wonderful in this regard. 
Joseph Audio speakers disappear and image with the best of them.  I also like ProAc and Vandersteen for these reasons, but there's just something special in this regard from JA speakers.  Also agree Audio Physic speakers excel in this area, and Avalon speakers also impressed me in this regard.  I think Verity Audio and Gershman speakers are also very good in these areas as well. 
Dynaudio, Proac, Harbeth. Setup and room are super important