Most of the Compositing that shake does is With Film scans(2k-4k). At least that I do. The FCP intergration is for editors that have composites that require more tools than FCP has to offer. You can also bring in PSD's with the layers intact with some success. Just remember that shake is in no way iMovie with compositing tools. Compositing is not a easy thing to learn. But don't get me wrong you can learn alot about images, and how to put them together. Learning new ways to intergrate images(adds, subtracts, multiply, outside, inside). All things that you can apply to photography and other graphics work. Very good skills to have.