I have Android 5.0 on my Nexus 7. You can read the many reviews available online for a more complete picture of 5.0 Lollipop, but my personal opinion is that it isn’t a huge leap forward from Android 4.4. There are UI differences, the material design looks nice, and it runs well for the most part. I have experienced two issues with 5.0 though: there was a problem with video playback on YouTube (perhaps elsewhere as well, but I only experienced it on YouTube) that has since been patched in an update, and there is a memory leak issue that can cause the OS to shut down apps. I would wait until the memory leak issue is addressed before upgrading. You really aren’t missing anything earth shattering with 5.0. It’s a generally nice evolutionary update of Android, not a revolutionary new version of the OS.