There are a few criteria.

I'll start off by saying that a lock-on is probably the best to hunt out of. There are a few advantages - no set up time (once it's set), no carrying stuff in/out, you can hang it in some branches for cover.

Now - here's the dirt on lock-ons. They get stolen. Often. They're also a huge pain to hang up. (you really won't be able to change positions daily)

A climber is my usual, b/c I hunt a lot of hardwood forests, where the tree canopy is 50 ft. high. It's easy to find a white oak or a wild cherrythat is suitable to climb, with little limb-sawing required.

If you want to hunt a field edge or scrub brush, the tree canopy is usually low, and you'll have a really hard time finding a "climbable" tree. You'll need a lock-on.

My advice is that if you're hunting somewhere where your lock-on is safe, take a trip out and look around at your likely hunting spots. You'll see whether or not there are good climber trees standing around.

Either way, a folding limbsaw and a safety belt are a must, so make sure you have those before the opener.

Also be advised that lock-on's require either climbing sticks or screw-in steps. Screwing in those steps isn't easy and is best aided by a cordless drill, some daredevil-monkey-type climbingand no fear of heights. Climbing sticks are probably easier to use, but also a theft risk.

I'm part monkey, so I hang my lock-ons so that nobody else would even attempt getting into 'em. My first step is always about 8 feet off the ground.They're usually concealed in the crotch of a tree anyway.

They both have their advantages, but a climber is completely useless if you can't find a tree to climb.