I have had my 18WSM for about 10 years, so there was no 22WSM when I got my 18WSM. But I will be getting a 22WSM soon and it doesn't really have anything to do with capacity. It has to do with the size of the grates and being able to put ribs and full size packers in it without cramming, bending, etc. them to get them under the lid and have them hang over the water pan edge when using the bottom grate. I just want a much easier and joyful experience when I cook 4,5,6 racks of ribs or a full packer since even with rib racks it is a PITA on the 18WSM. Also, when using the bottom grate, I don't like having the meat go beyond the edge of the water pan since the heat is much higher in this outer ring and therefore cooks the meat faster on the edge. And when I load up the 18WSM with butts or chickens, it is unavoidable, so having much bigger grates of the 22WSM is a big bonus here.
Will I never use my 18WSM again?....heck no, I will most likely use it more than the 22WSM, but when I want to do ribs or packers, it will be automatic. Is it necessary to have more room for these, no but I know myself and if I enjoy something more, I will do it more often. Yes it is more money, but for me it is worth it to enjoy the experience and also make it easier for me to cook ribs and packers more often.
Good luck,
Kg
Will I never use my 18WSM again?....heck no, I will most likely use it more than the 22WSM, but when I want to do ribs or packers, it will be automatic. Is it necessary to have more room for these, no but I know myself and if I enjoy something more, I will do it more often. Yes it is more money, but for me it is worth it to enjoy the experience and also make it easier for me to cook ribs and packers more often.
Good luck,
Kg