Wow, that would depend on your app. In our case I wouldn't want to do this it because all of our endpoints point to other acceptance environments, which might or might not be available with prod setup. Email is not being sent out in our cause from acceptance (configuration). Your SSO configuration could be different with another (smaller) set of users/groups which are allowed access. Your scaling/instances and database/file storage could be different. Contants, scheduled events, custom runtime settings and/or custom domains..
Lot's of things apart from the data aspect which could differ..
No difference to my knowledge. Just make sure nothing gets dropped while moving the data back and forth between environments (someone submitting a request after the backup is completed and the environment is still running for example), and as Sjors Schultz said, you need to make sure all integrations are moved correctly and timely as well. The URL will also differ, and you need to remember setting all the needed configurations in the new environment (network, constants, scheduled events, custom Environment Variables, who has access to backups and logs, etc...).
You might want to look for a way to keep an instance running while another is being restarted (not sure if it is doable on the cloud) if your environment has multiple instances. You can contact Mendix support to inquire about this.
Of course, if anything happens which requires Mendix Support Team then I’m not sure if they will treat it as Urgent/Critical as they would if it was deployed to the production environment.
I’d confirm with Mendix Support anyway if I were in your position. Just to be sure/safe.