I am in this camp. I do not like sand. Not in the coop nor in the run. No matter how much I scooped, I could never get all the poo out and after a few months, it looked like a giant litter box. It was also very cold in the winter time. Removing it wasn't much fun either. I would shudder to think of it in the run where it could get wet. Sorry, but I am not a fan.
X3! It might be fine for small coops in arid climates...but eventually it becomes saturated with pulverized poop and will stink to high heaven if it gets damp/wet.
Learned that using it in the brooder, was nasty.
If you search enough threads you'll find plenty more who learned that the hard way
(folks who have used it for
more than one or two seasons).
I learned a
lot about sand while making my own concrete mixes for sculpture years ago; I used different cements, different sands, different admixes.
All the colloquial and common names for sand(river, construction, play, blahblahblah) are worthless, there's no standards, you've got to look at it
very closely to know what you're getting. Made a
huge difference in my concrete mixes, so I had to study it, and also applies when using for chickens.