The products are very poorly designed. We got the 28x8x12 round top.
During install the parts didn't fit together right (one pipe had to be redrilled it was so off. Another had to be thrown away and we had to wait for a replacement).
The door was always impossible to open, and then the zippers all broke within 2 months.
Finally it blew to pieces during a stormy day. No amount of bracing was going to hold it to together. Even with a variety of extra anchors cemented in all around it, with it sheltered by a shed and a fence, and a truck, and then surrounded inside and out with hay bales, it just picked up like a kite and ripped to peices.
Didn't make it even 8 months.
We left the back of the frame hanging uncovered for the last year and finally went to survey the damage today. The back cover is still hanging from that side and I was shocked to see the material. It was paper thin, faded, and cracked. If the shelter had stood up the storm, it would have been rendered useless by now just because the fabric degraded so badly. Very disappointing. I had expected it to fail fairly quickly, but I was thinking something like 5 years - not 8 months.