Magico S5 or Rockport Atria

win, win, win. You could do what I do and wait til there's used models on the market and demo a pair as long as you want. Buy all 3 sell all 3 and now that you're confident on the one you like best each company will replace them with new models and you can start all over again.

The Magico A5 will be better than all of these, at a lower cost (if you are referring to the original S5).

My biggest concern with these two speakers is that I end up with listener fatigue after long listening sessions.

If you want better sound quality than the Magicos, you need to be prepared to spend more money.You would need to look at the Vimbergs. They cost more.

When I was at RMAF I listened to the Magico S5, I believe the Rockport and Atria and the Joseph Audio Pearls.  Granted these were not long listening sessions but if I had to choose it would be Joseph Audio, Rockport and Magico.  It just depends on the attributes you are looking for in a speaker.  I tend to like speakers that aren't as analytical.

I’ve heard both the Q7 and Aviors and both were excellent.  If I were to sum them up I’d say the Magico sound skews more neutral thought not cold sounding at all while Rockport skews more musical though still with great detail.  Given your preferences I’d go with Rockport, and as Andy Payor also uses Gryphon Class-A amps to voice his speakers I’d think they’d match very well with your Pass amp as well.

I have to say though that at this price level I’d take Joseph Audio Pearls over either as to me they combine the musicality and neutrality of both with even better imaging and 3D soundstage.  I also think the Pearl’s silk-dome Seas tweeter could potentially be a little less likely to induce fatigue over the beryllium tweets in the other two, but as they are also extremely refined it could be a non issue all around.  But that’s me and your two choices are both outstanding regardless, and I’m sure you’ll be thrilled with whatever you ultimately choose.  Hope this helps, and best of luck.