Well, you would have to compare the spec radials to spec gravity tires, not grid trail since they are gravity tires and would weigh the same. I know a bunch of people on Schwalbe trail radials and they love them. Same with Schwalbe gravity. Only had one friend who complained about them being slow and giving up on them. And he def was on trails because he doesn't ever us dh casing, even when he really, really should. But he has lucked out so far, so good for him.