Agreed, it is easy to try and choose whatever sounds best to you. That's obviously a subjective thing though, so to satisfy my curiosity, I plotted many REW graphs for various XO settings for my HT and two 2 Ch stereo systems to see the objective side. In every case, I found that with XO set to 40 or 60, the 15 to 200 Hz response for the L+R+Sub(s) did not look good, with or without XT32 on, whereas 80, 90, or 100, even 110 Hz yielded the flattest curves. Of the 3 systems, two are good size tower, one being the KEF R900, the 3rd ones are bookshelves, the LS50s. It looked obvious to me the way the L/R/Subs in both rooms interacted with each other to produce negative results, so bad that XT32 could not improve nearly enough, unless helped with higher XO settings.