I'm around 220 pounds and 6ft3. I use a Suntour on one of my touring bikes. I bought it originally when I was getting a bit of back pain. I set the pre-load fairly high so that in normal use it wasn't moving but if I hit a large bump it gave a bit of cushion. Obviously really big bumps you avoid or stand out the saddle. I've now gone back to a standard post as my back has improved and the benefit is no longer worth the extra 500g.

As part of a weght reduction I saved nearly a kilo with a new seat post, lighter pedals, and a lighter rear wheel.

I also have a Cane Creek Thudbuster on my MTB. That gives a much softer ride. For outright comfort it is the one to go for. There is a bit of back to front movement as well as up and down but you get used to it.