It's nice to have a second database to test things out. You can move things from the old dB to the new one that CPG is using and then you'll have a clear dB if you want to do auto installs in the future. You would just have to edit the files that access the dB to match the new dB login.
Before you do anything, I recommend doing the upgrade. You can go through the list to see if it's worth it, but I think it is. It started out for me that I needed EXIF and the new version had built-in support for it. The thing was I upgraded after making lots of custom changes so it was a huge pain
, but it was still worth the upgrade.
However, with no custom changes, the upgrade shouldn't be a problem. I had to add the new code around my custom template.