I usually go 80/85 or maybe 80/90 if I'm going to be out all day on 28mm schwalbe pro 1 (which measure right at 28mm on my WH6800 shimano wheels). i'm 225 right now.

It is noticeably more comfy than 100-110 that I ride on clinchers but not low enough to be squishy. If I stand up to power up a hill, I do feel a little bouncing out of the rear tire but it's tolerable.