I used to use my Weber kettle for smoking and it did a fine job. Long, low temp smokes for several hours without refueling.
I needed a little more capacity so I built myself a UDS (Google: ugly drum smoker) last summer from a reconditioned food grade 55 gallon drum. It is very fuel efficient with either lump or charcoal briquettes, toss in a few wood chunks for smoke and it can easily cruise at smoking temps for 12+ hours. Virtually zero maintenance and very easy cleanup.
If I were looking for another smoker I would build another one of the same.
It's a fun DIY project with readily available parts if you're into that sort of thing. :))