The stacker is a must have it will fit on all other 18" grills. The charcoal ring is a larger diameter the charcoal ring fits inside it, meaning more charcoal. A must have if you get the stacker. I don't know if the pie pan still comes with it.
If you're not having any trouble with the factory door then the SS door is not needed. The "bling banshees" will definitely chime in on this. Overall I'd say go for it.
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