Agreed. My work monitor is a 32 or 34" ultrawide. It works well but I would really like more vertical real estate. I'm definitely shopping for 32-34" 4k displays right now.
Looks nice also, but I already have a 4k 32" Eizo Flexscan that I'm happy with - I'm after the 4:3 aspect ratio, everything just seems to go wider and wider these days.
Vertical is the reason I haven't upgraded from dual 1920x1200 (but of the time single anyway). Although I'm looking at 1440p mainly for 120hz+. (1440p at 30+")