I've been enjoying my new Large Egg over the last three weeks and I have a question about maintaining the cooking grid. I've upgraded from using a Weber kettle the last 9 years and at the end of each cook I would scrape it down with a brush and let it burn off while the charcoal died down. However over time it would start to rust and once a year I'd have to go buy a new one because the surface was so bad. Will the Egg's grid hold out better? Is there anything I need to do to maintain the surface?