I don't have one, but I've used one a few times. They seem to produce a pretty even heat and hold/maintain the temperature well, even if only a low heat once the shell warms up. My issues with them are the size(s) and weight. If you ever have to move it, a certain amount of care for yourself and the egg needs to be taken. You don't want that bad larry tipping over! The other issue I have is the size... Quite often if I'm grilling or smoking, it's for enough people that I don't find the Green Eggs to be very practical. ~ That's my two-cents... take it, or leave. I won't be offended either way