I picked up an Ikea Markus, under $200 at the time, because of its strong showing on a Lifehacker poll [1] and it was the budget pick on Wirecutter [2], though it's since been superseded. I still like my Markus, but if we're shopping, I'd look at Wirecutter for ideas and advice.
[1] https://lifehacker.com/five-best-office-chairs-30776066
[2] https://thewirecutter.com/reviews/best-office-chair/