In most cases a vertical smoker will not put on bark
like an offset will, offset moves much more air through the cooker.
When you compair cooking times unattended the WSM
wins hands down. I have won 3 state championships cooking on them also.
To get more bark there are things you can do, run water pan using sand instead of water for heat sink.
You can also use wads of foil in place of water when you are going to do a higher temp cook.
Winds is a problem for most all vertical cookers but that can be offset with a wind break or wrap the cooker in a water heater blanket.
The main thing I get with a WSM
is sleep on long over night cooks, you can get 6 hours or more hours in most of the time.