I have been thinking about these, for awhile, since I heard about them...These things are 16-20 mil. thickness, and are designed to last 5 years, in the full sun. A 16'x 48', apparently the size of an average billboard, can be purchased for about $50 -$70 online. What a great way to build a hoop house. Apparently, they come with a sewn edge, which recieves a rope. No grommets. Anyone have experience with these?