I used a Niftyseat for a few years but found it very uncomfortable for my bony butt after an hour or so.
I made a few Torges seats, not bad but a little springy at times and not real comfortable for a long sit considering the limited padding I put on them.
A Summit Trophy Chair was next, a Cadillac for sure but heavy and a pain to carry on long hikes. In spite of it's short comings it has been my go to chair for long sits.
I have a hammock seat, nice and easy to carry on long turkey hunting treks.
I suspect a Milininum will be next on my list, they are so light.