volwrath@gmail.com Yeah, Observer Pro is just awesome. I have lots of trees, but have mapped out 7 sites around my property, and two on the shore of a nearby lake. I just pick an object from the catalogs and click "Compare Sites" and know instantly which site on the property will get the best view of the object for the longest time.
And it's so easy to trace the skyline at each site. 30 seconds with the iPad and I'm done.