Non fatigueing speaker under 1500

Second the vote for Spendors...the 2/3s or possibly a pair of 1/2s used. My experience is that the more you listen, the better they sound. Heavy, solid stands improve the sound of either speaker and I found that biwiring is beneficial with the 2/3s...don't know about the 1/2s.
Good Luck!

Soliloquy 5.3 Used or b-stock. Do a search for the various
reviews.
Sheldon

Spendor's new S6 is my vote.

Of your choices the Vandersteens are very good indeed. If after you purchase them, there is any residual hardness, look elsewhere in your setup! ( like Spendors also.)

I'd suggest a used pair of original Quad ESL's (the "57's") as among the most non-fatiguing speakers at any price, and if not Quads then Maggies.

Boxiness is a subtle but persistent source of listening fatigue, and it's fairly expensive to build boxes that don't sound like boxes. So in your price range, if non-fatiguing is the primary criteria, I enthusiastically recommend dipoles such as the Quads or Maggies.

The Maggies are more much forgiving of listening position, while the Quads are a bit more forgiving of speaker position. The Quads like low-power (usually tubes), and the Maggies like fairly high power. The Maggies don't really come to life at low volume levels like the Quads do.

On the other hand, if you gotta have boxes, the Vandies would be a good choice.