I hunt both ground blinds and climbers and it depends on the situation.
Ground blind
Pros- easy to get in and out of,
can sleep without worrying about falling out of tree,
good when the weather is incliment,
and an option when you can't find a tree to climb.
Cons-
restricted field of vision,
wary deer will always know where the blind is and be wary of it regardless of how well you have brushed it in, and how long it has been there,
brush in has to be refreshed periodically.
Climber/tree stand
Pros-Climbers are portable enough that you could hunt several hunt sites in as many days,
less restrictive field of vision and the ability to see over brush and smaller trees to prepare for a shot,
less claustrophobic
Cons-
You have to find a tree that your stand will fit on,
you have to climb the tree,
not as easy to sleep,
not comfortable when raining, snowing, or really cold,
more chance of injurying yourself.