I researched bike catalogs and the airless tire web sites to make a weight comparison.

For the mid grade tires (700 X 23) and tubes I run on my road bike the airless tire weighs three grams more per tire. The equivalent pressure of the airless is ninety psi, and I run 100 front 110 rear so maybe the airless would have more rolling resistance.

On my mountain bike the equivalent airless tire weighs 169 grams more per tire, and the equivalent pressure is the same as what I use in my tires. So 338 more grams per bike; I don't think I would notice that. Same rolling resistance **********?