Some of the popular propane smokers are rated in the area of 10,000- 18,000 BTU. That's plenty for a smoker. If you'll be doing grillin, or deep frying, or shrimp boils, you'd be happy with a much higher rating on something other than a smoker. My old Brinkman 3 in 1 bullet is rated at 170,000 BTU, and that thing has burnt the paint off it's frame at times!