^^^^^^ This is interesting to me as well. I haven't eaten off of a Kamado, but all of the bragging I hear about how little fuel they use makes me wonder if users end up with a small, smudgy fire and not-so-tasty food. I know my WSM is not super-efficient (lots of air leaks, heat loss, etc.) but it gives me a hot fire and clean smoke, which means tasty foods. When I was loading up my WSM to keep it working for long periods with little addition of fuel, my food wasn't nearly as good. These days, I mostly have all my vents entirely open, and my food tastes better than ever.
Also, for the record: if the kind folks at Weber want to share a promotional Summit with me, I will never say 'no'. It would probably become my primary cooker. But I think I might always miss having the old-fashioned offset lid vent, which allows me to direct heat/smoke over my food with greater precision. I think the Summit would work well for direct cooks and smokes (it would kick ass for pizza!), but I wonder how it does for indirect cooks.