I once visited a chiropractor who asked me to stand in front of him so he could assess what he needed to straighten first. At that stage he’d asked no questions about what I did for a living. Before he even laid hands on me he guessed that I was a helicopter pilot from my posture (main problems being crooked neck, spinal twist and drooping left shoulder).
I never found an RAF Helicopter with anything like a comfortable seat, in all my time flying them. In my early days on the Puma, most of the seat cushions had gone completely flat so there was no padding under your behind and I flew sitting on a pack of maps much of the time until the seat bases were modified to take a backside shaped dinghy/survival container, which also raised the sitting height. Unfortunately they didn’t raise the rear seat belt attachment point, so the tighter you had the shoulder harness, the more you were forced into a crouched down position because the straps went upwards to go over your shoulders. A further mod was done to raise the attachment point when it was realised that there was no forward restraint in a crash until the strap went straight but by then you would be bent in half. The armoured seat was far better for comfort but I reckon in a crash the armoured breast plate would break my jaw, if nothing worse.
Sikorsky did a much better job with the S-76 and S-70 (but the Whirlwind and Wessex were designed for someone of very different shape and dimensions to me). Agusta did quite a good job with the A109. AeroSpatiale not too bad with the AS355.