I store my Magma grill in the midcabin under the bed. After it cools I place it in a garbage bag, then inside the storage bag. No smell, out of the way. It's the only way I could find to store that beast of a grill...short of putting it in the engine room.
Which model? I have one of the smaller magmas that fits nicely in the lazarette but I've been thinking of going with a larger grill now that we have a bigger boat.