I guess I should add a picture of my collection.
I started with an 18.5 in '09 and loved it. But I found that filling it up meant I would smoke less since I'm mostly cooking for SWMBO and myself. Plus I wanted to test different smoking woods and didn't want to commit a huge amount of meat to a single smoking wood (nor did I want to run a mostly empty smoker.) Then I saw a thread on TVWBB on the mini-WSM and finally put that Smokey Joe to work. And for a couple more years this was sufficient. Except when I want to cook 6 racks of spares, I found that the 18.5 was just not quite big enough. About that time a 22.5 showed up on Craigslist for $150 so I jumped on it. The family is now complete.
I also have a plan for a hanging meat mod (AKA PBC mod) and if I get it working, I'll share with everyone here. I may do some other experimenting. I'm not sure of the lack of water bowl or hanging of the meat is what makes the difference and I hope to find out.
I love the heck out of my Weber smokers. Of course one does not live by smokers alone and I have kettles running from 18.5 through 26.
And I have a couple Weber gassers to round out the collection. SWMBO thinks I'm crazy but figures this is better than chasing wild women.