Some decent options in this thread, I thought I'd add some general advice, which I could have used in the past. Firstly, figure out if you want / need a neck rest. This turns out to be important for me, and I would not want a chair that doesn't have one (this point could be expanded with exceptions). Next, adjustability is key. Some things are standard (backrest angle, height), but many are rarer. For me, being able…
For OP: Personally I don't have a super fancy chair, cost me about 80-100 euro IIRC but don't even know what "brand" it is. Generic office chair :P