I have a nice pottery barn loveseat in my guestroom that is a pullout. It was the first time I had seen a pullout that didn't have all of the bars and it has a genuine mattress. It's extremely comfortable. Of course there is one bar in the middle to support the mattress, but you don't feel it. The mattress is firm yet folds in half very easily.

On the hotel side, as others mentioned lots of places have sofa beds. One I have heard where they are actually fairly comfy is Dorado Beach, and I believe every single accommodation option there has one.