jalama,
I've got an Outcast Fish Cat with an inflatable seat. I like it and would recommend it but I'm neither tall nor fat. I like the way the inflatable seat holds me up out of the water in that it makes casting easier. I also have a Caddis tube with a mesh seat that lets my butt set down in the water that I don't like as well.
I have fished with Poke and the pontoon he's got is really nice. It may be my next toy. You can kick around in it or use the oars. He can really move around in it fast when changing spots.