Mainsheet Cordage Material

On my recently purchased 5372, the mainsheet is very rough and leave blue fuzz all over the place. It has suffered bad sun degradation. What mainsheet material do you find works best nowadays....I want to replace it and see FS, Inc carries a selection. Also why is it so important that it floats....do you really let it lie in the water when running in light air or just want a very non-absorbing material so it does not get soaking wet and heavy. Thanks a bunch, Jim