I have 2 18 inchers
One I bought for 160 about ten years ago, it was a floor model at a hardware store and was missing the door knob-weber sent me one for free.
I "accidentally" modded this one up. I bent the door one day and it was cooking pretty hot. Out of frustration I sealed the door up with 4 inch aluminum tape. Well after one cook that tape became welded to the cooker, couldn't get it off.
So I bought a guru and started using that exclusively with the wsm. With that door sealed I can get 18 hours at 225 on SIX pounds of charcoal. Problen is the thing burn funny now and will extinguish itself sometimes without the guru.
Good fortune. I am perusing craigslist one day and there is an 18" wsm!
A) Its one durn mile from my house;
B) Listed as new/unused in box-"Won at golf tournament. Don't need one, I have a nice gas grill"; and if I'm lyin I'm dyin,
C) Fifty dollars!!!
Taa Daaa. I now have my hopped up model as well as a stocker.
I have since bought an egg, which I love, but I couldn't imagine letting the Webers go. Its just one of those products-it works soo damn well it is just something you keep. I'm building a real covered patio this summer and I MIGHT lose the taped up one, but I will always have one.