For me, the factors to consider on a smoker purchase
1) Fuel source - stick burner or hardwood lump
2) Insulation - kamados are great, cabinet smokers too for more capacity. Amazing fuel usage and temperature control. If you're getting a barrel cooker, make sure the steel is at least 1/4" thick and the doors close tight. I don't like the cheaper barrel smokers. You're better off going vertical in the sub $1000 price range IMO.
3) Mobility - Is this for the back yard? Catering/competition events? Some things are easier to move, some even are mounted on their own wheels
5) How easy it is to reload fuel
7) Availability- A lot of the great smoker fabricators expect local pickup. BBQ guys half way across the country to pick up their new rigs.