I have 2 cats and one litter box in the bathroom.
I use a scooping cat litter (not sure if I can say the brand here or not, so I won't). But it's fine like sand. I scoop at least 2 times per day not only for my cats' sake, but also for my own in order to avoid dirty litter box smell. It doesn't touch the wall on any side, and the closest it sits to the wall is about 5" on one side, so they are free to face any way they like.
The only time my oldest cat pooped outside the litter box was when she gave me the look of "I need to go. Add more litter to the box" type look, hehe. It was really low and I purposefully let it get low so that I could clean it without throwing out a bunch of good litter. She kept coming and checking out my progress, and I could tell she needed to go quite badly, but I guess it took me too long to empty it, disinfect it, dry it and refill it, because by the time I was done, she had left a little gift in the closet.
I didn't get upset because she did tell me she had to go and gave me fair warning, hehe. Now I don't wait quite as long to do a complete litter change and disinfection