Thank you all for your responses. I may not have used the correct term saying the "Bimini Cover", so in layman's language I am referring to the big black cover that snaps on the side of the boat and covers the whole interior and does have 3 poles that hold it up so the water runs off or is supposed.
The bimini cover is that thing you can raise up for shade while out on the boat. As for your mooring or playpen cover (what it sounds like you are really talking about), there were some nice ideas above.
Our Benny used to be under a huge Sunbrella canopy when we kept it on a lift the first two seasons. I got rid of the lift/canopy this year and now have it up out of the water on its Sea Legs when not in use. That means I am down to just using the mooring cover for rain and other environmental protection. It does handle about 95% of the rain. I still can get a little dampness inside of it, and particularly around some seat edges.
And although barely used these past three summers due to the former canopy, our cover already has two issues that are likely warranty related (tie string for securing it around 1 of my bimini supports just pulled right off the first time I tried to tie it up, and I am seeing a little fraying and can see “sunlight” through the black cover at one of my pole support vent caps).
Not sure I want to mess with any sort of warranty claim, or snap realignment issues over such minor things now. BUT if leaking begins to happen at any of those points or new problems develop that compromise it keeping water out, then I’ll need to follow up with my dealer for a warranty fix or replacement.
Overall, I like how light and easy to handle the cover is with its current material. However, it does seem flimsy and non-durable. Pros and Cons I suppose. If it were super durable like Sunbrella, it wouldn’t be nearly as light and easy to handle - and with my back these days, I do like light and easy to handle.

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