Thanks for creating this thread AVUser. I appreciate you sharing your experiences with different sets of speakers and trying to be objective about your listening goals, and impressions.
I added the 60Xts in late November, as my goal was upgrading from some vintage Def Techs (BP8s), and have been enjoying them immensely. I wanted to get some speakers that were more pleasant for 2 ch music listening, but didn't want to give up that large soundstage and spaciousness of the DTs (Their bi-polar design is great for this, but mediocre for imaging, clarity and balance for music).
I did have the 40s (which I returned) and I liked them both in my setup. Your impressions mirror my own, except I did audition them in my own living room. 40s were punchy, with great midrange, and excitement, but lacked scale neutrality and that wide soundstage, compared to the 60s. My final decision came down to the center channel (which is so critical to HT), since the 60Xts matched better with the 50XT center (larger tweeter). So remember to keep that in mind too, a high quality, and cost effective matching center, that can hang with the fronts.
Ultimately, I felt the 60s met the goal I had of maintaining that large scale sound of the front stage, and running them full range for 2ch music has resulted in a pleasant, full, and luxurious listening experience for all types of music.
Some other notes-
-Running the 60XTs separately on a Parasound A21, and remaining channels on an A51.
-Dirac helped me tame some of the bloated bass I was getting in my 13x17 room (right speaker close to wall)
-Also running the front speakers as large, and the other remaining bed channels crossed at 80hz with 2 PB16s
-50XT is a great match and keeps up with the front stage