Set expiration dates for access to Google Drive, Docs, Sheets, and Slides files

I just read Google's Blog and they talked about a new feature when sharing files with others.  You will be able to set an expiration date when give someone commenting or viewing access to a file; you will not be able to do this to someone you give editing access too.  It will probably be rolling out around the end of the school year, so you can really take advantage of it next school year.

I like this because I often give students access to view a file of mine for a specific reason, but don't really want them having access to it for an extended period of time.  Yes, they might be able to make a copy of it for themselves, but you can turn off that feature.

What are your thoughts about this update?