If using the Sig floats, go beyond their recommendation for glassing the floats. Use 2 oz. glass on the floats bottom and sides as well. I know it sounds like overkill but the vibration of running over choppy water and a few hard landings will cause the sides to split out. My set made this way is over a dozen years old. If you do it right you will not gain that much weight. If you don't do this but two sets of floats, thats what I had to do. I also start the bottom by laying a strip down the center. It starts at the front bottom of the float as a long skinny triangle. The point at the tip and it ends at the step where it is the full width if the step. When finished, glass over the area with a full width of cloth. This provides a wear strip for those who can't resist beaching the aircraft