Do you store your sewer hose in your bumper? That is the quickest way I know to ruin your sewer hose. As rust develops inside the bumper, each time you push your hose in it cuts it like a razor. Store it in a plastic tub and it will last a LONG time. I have been using my Rhino hose for 6 seasons now and it is still as good as new.
Just my 2 cents.