I have the same model grill and love it, about 8 seasons so far with mine and don't seeing it needing replaced for another 10-15 years. Just keep the side firebox painted and oiled with vegetable oil, and the cast iron grates oiled, and the ashes dumped frequently and you should be good!
Thanks for the advice, you literally pour vegetable oil on the firebox? Mine is starting to rust again, I was going to grind it down to the metal again and repaint it this year. I found it in a trash heap at the DOT station in town and fixed it up!