Just to run to the store and back I had 28s then went to the 25s that I am running now. As soon as they start showing wear it's back to 28s.

I swear that the backside "sees" a bigger difference than the little bit that the eyes do.

I'm thinking about going ahead with a 28 on the rear. That's where most of the weight is. The rear does most of the work and that is where I seem to feel the biggest difference in the tires. The front tire doesn't do much more than keep the fork legs from digging into the pavement, until you turn.