"not afraid to fuck up anything" likely refers more to the ability to rollback the system to any (non-deleted) previous revision of the system configuration, directly from the bootloader, which means you can easily recover even from a broken kernel.
This applies regardless of whether you are packaging/updating something in the package set yourself, or using something that someone else packaged.
No, you can get the installer directly from the NVidia website, but only for selected platforms. If you're on a different platform, you'll have to wait until somebody ported (read: hacked) the release (or do it yourself).
