It seems that Seaplane and i have a mutual admiration society going:
If you feel that the GP60 floats are heavy, or if (when) they leak and get even heavier while they decay from within, Seaplane makes some pretty darned nice foam-core floats that look a LOT like the GP floats, but are lighter and will never leak. I cut foam floats, too, but I'm not disposed to sheet them for you like Seaplane will.