For me, the Depth of Field feature of the Premium Render setting is what makes it worth it. Finally I am able to create a feeling of depth by throwing the background out of focus. It just lets you add more drama to your scenes. The tree lab is okay, although the more trees you use, the slower the render gets. I also own the Delvin Forest CD, so I'm up to my ears in trees of all kinds anyway. Network rendering is incredibly useful for doing animation, and the metaballs are just priceless. Bryce5 is definately worth the upgrade.