The people that are very serious about it, and who win BBQ competitions, pretty much all use an offset smoker like this style. But these are mostly overkill for the average person, and they're only for smoking. You're not grilling burgers or steaks on these. Many of these are either homemade or custom solutions made by a welder, or bought for thousands of dollars.
The next best option most people advocate are the kamado style ceramic smokers/grills like the big green egg and kamado Joe. These can get you results that are almost as good as an offset smoker, with some people claiming they're every bit as good. You can also bake pizzas on these and can grill burgers and steaks too. I wouldn't underestimate the value of being able to grill a steak on these. You can make the best steak you'll ever eat on one of these things. You can get it hot enough to sear both sides, then drop the temp and move them away from the flames over indirect heat and just sit there in smoke for however long you want. The steaks these things are capable of cooking are insane! Burgers too. A good smokey burger is amazing. These grills are the best option for a good steak of any of the smokers. They can get super hot, unlike an offset smoker. They also maintain consistent temperatures better than any other solution because of the insulation the ceramic provides. The downside is that these are expensive. Usually $1500+ for the good ones. There are some made in China ones that Costco sells for around $700 though. People say they're pretty good. These things are insanely heavy though.
Another great option is the Weber Smokey Mountain that a few people liked above. They're a lot cheaper ($400 or so depending on the size) than the ceramic ones, but are capable of producing some really awesome results. Pretty much as good of results as you'd get on the ceramic. But they don't maintain temperatures quite as well. They require a little more babysitting, and they won't last quite as long. But they're much cheaper and a hell of a lot easier to move around.
Another option that a lot of people really like are the pellet grills like Traeger, Yoder, and Green Mountain. These range quite a bit in price and quality, but they all are super easy to use and maintain temperatures automatically for you. You just set it and forget it. But your meat is smoked using pellets, not wood and lump charcoal. But that doesn't mean it won't still taste great. You won't win competitions with a Traeger, but you can sure still make some amazing dinners, and it's pretty damn convenient. You can also cook burgers and steaks on these, although they won't get as hot as a ceramic egg style will. Some people say they don't get hot enough to make a perfect steak, but they can still make a good one. These range between $600 to $800 unless you want a Yoder, which is like $1500+. Oh, and you'll need an electrical outlet with these so you can run the pellet firebox and temperature controller.
There are also some pretty cool vertical stack style smokers that some people use. Often homemade solutions where people hack old refrigerators or freezers, although there are some commercial units like these as well. You can get good results from these as well, although you're not going to be grilling burgers or steaks on them. But most people don't want these sitting on their back porch and end up going with one of the options above.
Then there are electric smokers. These usually arrive with a case of Bud Light and a thank you letter.
