Every smoker has its pros and cons. Bottom line, each is a smoky oven, but that's about as close as they get to being similar.
Is the smoker easy or hard to use?
Is that use hands on or off?
Is it suitable for a beginner, or does it require experience and cooking instincts?
Does it deliver a great smoke flavor, or something lighter tasting?
Is the fuel available, cheap, or expensive?
Is it going to be used just for smoking, or for grilling, too?
Does it have mechanical or electrical failure points? If so, what's the reliability?
How much will the buyer smoke on average? How often?
Will the individual only hot smoke, or cold smoke, too?
What's the top of their budget? (Price does not equal a successful smoke. If it did, anyone could buy a $2000 set of golf clubs and play like a pro).
Unfortunately, many people don't want questions, they want answers, but are often surprised or baffled by results they didn't anticipate after making a purchase.
Personally, the
Weber Kettle and
WSM gave me the most satisfying combination of answers. Started with
the Kettle, and moved to the
WSM six months later.