Fly mask, Fly sheet, Fly Spay?

We ALWAYS use fly masks on our horses. They're affective and worth the little money that they cost. I also use SWAT (clear/white cream, doesn't wash off very easily). For my grey horse, she is easily irritated by flies and in order to prevent skin cancer I got her a UV Fly Sheet. It has worked wonders, especially since she now has stitches on her hip. Now the flies can't bug it and she can't get dirt in the sutures.