I have an 18 wsm and am a huge fan. Really versatile, easy to use. Can use it with a water pan, without, run it hot or low. And they can fit a lot of food, 2-3 butts in each rack, a decent size brisket, with the weber hanging rack you can hand 6 full racks of ribs pretty easily, 3-4 split chickens and I'm just talking about the 18. I can't think of any real issues that hold it back.