I play for really long amounts of time... 4-12 hours in a day sometimes. With my old 50 dollar special throne, I'd have back issues, and lose circulation in my legs after long stints.
I shelled out $130 for a Pork Pie memory foam seat, and it 100% solved both issues. It's literally like sitting on a comfy couch. My band mates call it my "drum sofa". The foam is so thick that it moves around just a bit and never bottoms out. The base of the throne is super solid and doesn't move at all. Only slight downside is that it's heavy and a pain to haul around to shows, at least compared to the old lighter throne... Nothing I really even need to mention.