I got the IKEA Bekant sit/stand L desk and I’ve been really satisfied with it. I alternate between computer chair and standing and don’t think a stool would provide enough comfort for me.
I had a carpenter build a desk for me at my preferred height, and use a stool when I don't want to stand.
The stool not providing enough comfort is a plus for me, as it naturally makes me to switch between standing and sitting throughout the day.
Additionally, the stool doesn't provide any back support, which has been great for me to force a better posture and get rid of back pain. (I probably still end up sitting 70% to 80% of my day, but that's good enough for me :)
