I've serously been considering the rock climbing gear. Does the fact that it attaches to the front of the belt cause any problems.
One thing I like about a basic saftey belt, is I feel like I'm almost strapped to the tree, as the link is short and at my back, I can lean against it a little. If I want to rotate in my tree, I can simply rotate the link around the belt. You can rotate 360 degrees if you want to.
However, I do want to be safe, I've got a wife and kids to think about.