I have an 18.5 WSM and I'm thinking about selling it. I can smoke on my kettle pretty darn well. And I don't need tons of real estate, which the 18.5 doesn't really provide anyway. The big difference to me seems to be when you open the lid of the WSM you lose your heat, but your coals aren't greatly affected. When you open the lid of your kettle, you lose your heat, and your coals get a rush of oxygen and start burning a little faster than you might like. Soooo, keep the lid closed and smoke away. WSMs are expensive, kettles are cheap. I did some pulled pork on a free kettle the other day, tasted just as great as on the $300 WSM.