I think with a little practice, and good airflow, a Kamado Cooker is every bit as stable as a WSM. I've done many a 12 hour cooks, pegged at 240-260°, with a variance of less than 10-15° either way on a Kamado. Not taking anything away from the WSM, it's a fine smoker. It would just be a challenge smoke something for 10+ hours on a WSM, then being it up to 500° and sear some steaks, afterwards, without adding a piece of charcoal, which is commonplace for a Kamado...