I have both. Started with the large. Worked great for two years. Then I realized most of the time I cook with it, there are people coming over and the demand for more space on the grid was present. Decided to buy the xl. Love the fact that I can get a full size foil pan on there. Then I bought the adjustable rig setup from cgs. That was the best investment for the xl there is. Can get a ton of food on there if needed and is very versatile in how you can set it up. Have gotten eight pork butts on there at one time. Didn't run out of charcoal either. It does use a little more that the large but nothing outrageous. After buying the xl, the large does get a bit lonely. But they do both get used the same time a lot too though.
Humphrey's Cubed Beast, XL BGE, UDS, and my trusty Weber Kettle. At your service...