I bought the full arrow system for my street triple and couldn't agree with you more. I could carry the box with the arrow system with one hand pretty easily. I put the stock system in the same box afterwards and was struggling to carry it with both arms.gotta be more than 15lbs.... i'd guess more like 25lbs lighter. the stock muffler in the back is very HEAVY !
you can pick up this whole system and hold it with one finger