Charlie, What I use is a bar stool with a swivel base. It is easy for me to sit in and you can lean back and relax when you need to. The bigest reson for getting this is my MIL owns the resturaunt, show the chair was free. If you have back problems you might want one with more padding and a back, this is one more thing good about these stools. Let us know what you end up with and how you like it.
Mine is a nice adjustible work stool with padded back as well as well padded rump pad. As for adjustment, I got it set where I like it and it stays there so why adjust(?) I guess I needed the adjustment to get it where I like it.
I went to a used office furniture store. Since there are many aerospace companies nearby, they always have nice padded stools with the pneumatic lift.
Got that was nearly new for $50. The only thing that would interfere with bench use would be arms, and mine came without. The comfort encourages me to work longer, rather than squirming or moving around the shop. Something with a back really helps eliminate aches and pains.
I don't know how much adjustment that you are looking for. I got one at Staples a couple of years ago that they had on sale for $25 for some reason or another and it has been great although I use it in my computer/TV room. It has arms that are detachable and adjust up pretty high for that type of chair. I wish now that I had bought two more for my work area.
A few months back Sears offered their shop stool on sale for about $35. It's height is adjustable, it has a padded back rest and seat, and rungs for your feet to rest. It is covered in a heavy vinyl. I have been pleased with it, especially the price after looking at some of the drafting stools costing $200 to $300 and more! If you want, I'll take a picture of it and post here.