I like both, but I get better arrow flight out of a 125 than a 100. And that is because I'm just a hair overspined with a 100 vs. 125, or at least I believe that. I put a 125gr ST Mag completely through the spine and through the chest of the "disabled BB" I shot this year, and with a little re-edging, it was back in my quiver and ready for service!!!!