I don't know if you have ordered yet @EggheadRalphbut I wanted to update.
Here's the reason to buy a 42. Check out this real estate inside. I bought 2 pork butts. One that I'm doing as just pulled pork BBQ and the other I am doing "Tacos Al Pastor". The smaller chunk of shoulder is the remainder / the portion I'm not using for Al Pastor on the 2nd pork butt. Check out how much real estate this thing has. I opened the grill up to test the pan I want to use for Al Pastor tonight. The thing will fit in here lengthwise! And I've only used 2/3 of the room - I still have room to get all the way down to the firebox if I need to reload. Note I don't even have the lower grate on so I can just get directly to the firebox.
Anyway, I'm personally glad I got the 42. Once all this lower temp stuff is done later, I'm going to put the lower grid right down above that fire and grill some chicken and vac seal for the week ahead. But in fact, I could grill at the same time as smoking if I wanted to (I just don't want to open the lid that often). Anyway - talk about versatility. The 42SBB is the ultimate in versatility and space. And it's an awesome smoker. Can't wait to taste the food tonight, the al pastor and the pulled pork!
As far as the charcoal usage for this cook, I am using the basket splitter 50/50, charcoal only on the left side. I have only loaded it with about 8lbs and I don't think I'm going to have to add any. I burned so much my first weekend b/c I ran it at 500 a very long time. It's not 3x what your big green egg uses, it's more like 2x, and you get at least 5x the room. Amazing machine this thing is.