Yeah I was just wondering if there were people that actually used backrests. Half the time I use a stool as a desk chair (it has wheels and a padded seat, kinda like this but with a fabric seat).
I use a stool like this for my home office and for practicing. I'm pretty much sitting on it 10 hours a day. For me it's comfortable, and I like the fact that it rolls and that there are no arms to get in the way (or for me to slouch on). They have versions with backs, too.
But...the comfort of seating is pretty much dependent on your body size and shape.
Depends on the game. With low drop ceiling where I prefer to play, games like Echo Arena and The Climb were causing me to punch the ceiling occasionally. So I tried Echo Arena seated yesterday and was surprised how well it worked as long as I could swivel freely.
So I just ordered this swivel stool as the back on my office chair was the only thing that was interfering with gameplay. https://www.amazon.com/gp/product/B0019QITHK/
I have an Obutto gaming cockpit that I use primarily for stuff like iRacing and Elite Dangerous.