Generally speaking you set the moving pin for 20 yards on the ground. then climb a tree and you should be able to shoot from the tree out to about 27- 30 yards depending on how fast your arrow is. That is if your form is good and you know how to shoot from an elevated position.

Downside to them is that they have moving parts and with moving parts comes another possible breakdown and most have a slight buzz when the arrow is released. I have used a couple of different ones and the slight buzz hasn't affected the outcome of the shot at all.