As a counterpoint to the HM Aeron I bought a brand new gaming version a few years back and had to send it back under the 14 day trial. The hard seat frame dug into my left thigh after a while and it just became uncomfortable . To say the least I was a bit gutted but at least I was not out of pocket. I ended up getting a really good deal on a Human Scale leather Freedom chair and it was just much better for me. The added plus being the head rest which the HM does not have unless you get a third party accessory and I use that quite a bit. Weirdly I’d had an old HM at work years ago and it was fine and I’ve not particularly changed size.