I just fitted a manta saddle.
It is interesting, but it definitely is not a pain in the arse!
I have done a few k’s on it on a regular bike, now to try it on my “shoprider” ebike (see below). I had tried it on a mountain bike with plenty of seat adjustment. I think it would be perfect on a mountain bike or cross bike with an upright riding position.
The levers pivot on the middle and move with your legs to give a wide area of weight distribution, and it certainly does that. When you are not pedalling it feels like a big tractor seat.
Like most things new it takes a bit of getting used to, you can slide around if you are unprepared.
Costs about the same as any quality saddle. Available from: mantasaddle.com