I am getting ready to open my pool this weekend and plan to bypass the SWG during initial start-up then putting it back on-line after getting any leftover Winter debris out of the system, introducing all of the opening chemicals, and getting the water back to normal. It looks like most pool supply stores sell a Saltwater Magic kit for monthly use. Does this really prolong the life of the salt cell? Is it worth doing, or just the supply co. whacking you for an extra $45/mo.?