Most of the session I sat off to the side and let everyone else take the good seats. I did have a chance to listen and measure some more after everyone had gone. I had not listenned to the Acculines before the session.
For the A1's, even though I did not have them all in the room at the same time, I much prefer the others you mentioned(although a comparison with the S-520 I think would be interesting), and in that strictly under $250/pr price range, I think I would lean toward the X-LS.....although there is going to be a change to the X-LS and the price is going up. During the session, I was tempted to take down my 170SE surrounds to compare, but I was too lazy and did not think it be worth the work....perhaps some other time.
Also, you mention the Era Design D5. I recently got to hear that one in my own room and was very impressed.