Do ergonomic chairs really help with back pain?

It really depends. I spent hours driving a taxi and my back hurt like crazy, but when I got into photography and was sitting in front of the computer, a taxi driver colleague recommended an ergonomic chair and it made quite a difference. That said, it's not magic, you gotta combine it with good habits like standing up every once in a while, stretching, and maintaining good posture. If your job is sitting all day like mine, it's worth investing in a good chair, but don't expect it to solve everything on its own.

It depends a lot on your posture and how much time you spend sitting, but a good ergonomic chair can help quite a bit if you combine it with movement (I for example go running in the mornings and that helps me way more than any chair). What I'd do is try one out before spending a ton of money, because there's people who spend a bunch and still end up with back pain.