My orange boy Scooter is a BIG cat. Very solid. He went to the vet in Aug to have his microchip implanted and he weighed 15 pounds. One month later he went back for his shots, and had gained .5 pounds. But the vet did say that he was not obese, and that he was just a very solid, healthy cat.
My parents have a light orange male that is large too, although because he is 12 he is not the size that he was when he was in his prime.