But wait, there's more. Canon's 300mm f/2.8 (next rental) costs about 1/2 as much, is said to have equal quality images, and weighs 1/2 as much. Weight is an issue with this: I put the lens in my snowboarding backpack this morning and it stuck out the top by about 5". Carrying it in a pack is way better than in the suitcase and you don't look like a tool doing it. Anyway, pay by the pound or mm: bhphoto.com has a used 1200mm Canon lens for sale that's $100/mm. Talk about envy..
(I blurred the background in CS3 to make the Coolpix images look better..)