I don't know about the Q5 and the validity of Stereophile measurements (you just dismissed them for the Quad and see Myles comment), but look at the Q3:Anyone knowing about the ESL63 knows you can not judge them on these very limited Stereophile measurements, as acknowledged in the review you quote. Do you really think that the Q5 is flat?
http://www.stereophile.com/content/magico-q5-loudspeaker-measurements
Regardless, this is getting silly, so I am going to bed.