If you get 25 years out of your marine vinyl, you got your monies worth! Don't use armour-all... absolute crap, it will actually dry out the marine vinyl. Also, don't use coppertone... it's for skin. I use a leather/vinyl cleaner after my boating. As for during the 120 degree days at Lake Havasu, I just keep em wiped down occasionally. I find if I fuss over them too much, you break down the stitching and end up stretching or abrading the vinyl.