I also have been looking for a cover for my 5th wheel. I have narrowed it down to two.
Classic Accessories OverDrive SkyShield™ Deluxe Tyvek® 5th Wheel Travel Trailer Cover
Classic AccessoriesGoldline Cover
GoldlineThey are close in cost but I am leaning toward the Classic Accessories cover. It is lightweight and has tension straps across the front and rear.
Be prepared for a lot of comments from those who say not to cover. I posted asking for feedback on these two covers and the only comments were not to cover.
If you get a properly sized cover, put it on correctly using foam etc. to protect all sharp points, and check on it regularly to make sure the straps are still tight there should not be any problems.
Good luck in your search!
Dave