That was my issue with multiple monitors years ago - I'd be cranking my neck over too often (looking at logs, etc). I vastly prefer an ultrawide where I can put logs / monitors on the side flexibly.
I have a 34 inch now, and feel like I could use more space - but it's nice to know there's an upper bound. Do you feel like there's still room to go beyond 40, or is that the sweet spot?
I honestly think 40 is the sweet spot.
3x27” high-PPI displays in portrait orientation is the winner and no one does it
The center display is always actually centered. The short edge of a high-PPI 27” screen is wide enough for actual normal width browser or IDE usage, but now you get much more vertical real estate on that window.
Not nearly as much neck movement as an ultra wide and since the entire array is pretty square, the neck movement is way more balanced.