This has been up for a week and makes a MAJOR difference in the temperature in my kennels. I bought the 90% and it would appear to be awfully close to that. Mine is basically flat and water does pool and sag a bit. But with morning sun it's gone, there will be no snow on it as I will remove it during the winter due to the severity of our winters here. It had a very strong smell when I first opened it so plan for that if using for an event. The next day the smell was gone though. Then there's the packaging... It was well enough wrapped but the box was as light a box as they make. Mine is 20'x30' and UPS said it was 28lbs. That's heafty, box it accordingly. I will update my review as needed.