I'm not really a hunting advocate, and probably ignorant on this topic, but wouldn't it be more fun to be on the ground and hunt old-school than sit in a tree?
The deer don't look up. Typically they'll walk right underneath you and never know you're there. I've even seen several types of footage showing a Buck rub their horns on a tree that someone was in filming them.
Plus, they have a serious sense of smell. Getting up in the air puts your scent up into the tree line rather than on the ground. If they smell something amiss...they wont come near.
Having said that, I do also have a portable blind to hunt at ground level if I feel like it or the terrain warrants it.