i've had some nice speakers over the years; they all imaged pretty well, but admittedly none of them performed at the level where i couldn't tell where in the room they were located. BUT, they all excelled at bringing out the textures of instruments/voices. now i could have, with the help of some friends, tried moving the speakers around inch by inch and perhaps gotten better results in getting them to disappear, but a decent stereo image has somehow been "enough" for me, especially considering the burden of moving 100-200 lbs. of speaker around.
NOW, usually it happens at the local wilson audio dealer that, regardless of the "wilson sound" good or bad, they can usually position them where i REALLY CANNOT TELL where they are. i just do not feel this alone is the last word in motivating a loudspeaker purchase. it certainly is uncanny, no doubt about it.