Best Practices? Should snapshot be activated 'network' or site-by-site in MultiSite?

I just installed 'Snapshot' on my MS w/ProSite's.

1) Should I:
a. Network Activate?
b. Activate on primary site and offer 'Snapshot' with upgraded level?

2) Can I force users to backup 'offsite' to one of the 3rd party options?

I would prefer users not be able to backup their sites
on our servers :slight_smile:

Thank you kindly and I hope you're all having a great day!