I have the Classic Accessories Poly 3. can be found for around $160.
But the major distributor that most mail order RV suppliers uses sent me 2 that were used/damaged before I got a new one :(.
one was ripped where someone pulled it too hard installing it, it was even duct taped back together and thrown back in box like it was a stuff sack.
The other you could see where someone turned on the heat and burnt a hole through a brand new cover, than returned it :).
3rd one was the charm.
I used a pool noodle cut up to fit over the down spouts and the corners of the solar panels.
Just go right over the antenna. But I did have 1 cut piece of pool noodle under each side of the antenna wing, but that was to stop the noise from the antenna moving in wind while camping. it survived the winter.

but I really want a metal roof over it.