I just strung it up and hosed it down, in the backyard. I give it a 7 out of 10. The fabric completely kept the water out.
Unfortunately, it is not 10' x 10'
It is 9'6" x 6'6"
My confusion came from misreading the label. It says it is designed to be used with a 10' x 10' gazebo. I mistook this for meaning that this piece was that size.
Also, there is a seam running the length of the fabric at about 5'. This will
Have to be sealed. There was some wicking along this seam.

For the price, it's a good asym tarp and I would call it great if it didn't have the seam in it.