I own and cook on both. I'm the guy with the ceramic grill store. If you want to talk through both cookers, feel free to give me a call. My favorite cooker is the xl and only three in my family. Here are a couple key comparisons from my experiences.
Long meat cuts, brisket and ribs, fit better on the xl's 24 inch wide grid. It's the square peg, round hole issue. Ribs can get 18" long and big briskets can get over 18" long.
By using some type of reducer with the xl, you can shrink the firebox for small grilling cooks. It's like grilling on a large or medium cooker.
One xl drawback is hot grilling cooks, steaks and such, with the dome mostly open. The handle being above the lump can get hot to the touch. I won't fire up the entire firebox for hot (searing) temp cooks. Cooker gets almost to hot to handle.
Managing lump with each cooker is a little different. It's no big deal, as you'll learn your cooker and not think twice on how you are doing it.
Cooking on a gird that is sitting on the fire ring is easier in the xl. The one inch shorter drop from the felt line (4" large vs. 3" xl) in the xl and the xl's wider diameter grid make it easier.
For long cooks (butts, brisket, ribs) the xl burns more fuel. Bigger cooker to heat. So if you're mostly smoking one or two meats, the large is a more fuel (lump) efficient choice. Same for searing inside the fire ring.
For the wife, the xl dome is cumbersome to open and close because of its weight. Same for her using some bge accessories.
My xl lump grate bows because of the heat. Not a big deal, more curious side affect than anything.
The drop from the top of the fire ring to the lump grate is shallower in the xl (approx. 7.5" xl vs. 9.5" large). Less room for lump on super long cooks but most of my cooks don't go over 15 hours. I've yet to run out of lump. Benefit of the shallower xl drop is with searing, closer to the lump, so can manage searing temps better.
In the xl, I can get three grids at or above the felt line. In the large, I can only get two at or above the felt line. I do ribs using the foil method, so more grids above the felt line make for bigger and easier cooks.
I don't wheel the eggs in a nest, so can't comment on movability. Broke the large in transport one time, so quit moving them.
Again, if you or anyone wants to talk, large vs. xl, feel free to contact me.
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