Migration from Google Apps: any hints, tips, recommendations?

I just completed over 7000 Google Apps (Mail, Vault, Drive and Sites) to Office 365 for one of our clients.

We used FastTrack services for mailboxes less than 40 GB. FastTrack uses the DELL tool that has limitations and we also identified some bugs that later got fixed but had to run delta passes for migrations as it did not move attachments prior to the bug being fixed. The tool had its limitation and could migrate about 2.5GB per day per user. For any mailboxes over 40GB we used BitTitan MigWiz and it did not have the throttling limitation as the DELL tool did.

For Google Sites to SharePoint Online we used Metalogix Content Migration tool for Google Apps (they no longer sell this tool). The tool was very limited in what it can do and based on numerous calls with the vendor. They mentioned its hard to keep up with the Google API changes which breaks functionality of the tool thus they are not planning any new development on the tool. Most of the Google Sites had data embeded into the sites which was pointing to users Google Drive and most content was also pointing to users Google Drive. We used ShareGate for this part of the migration and it worked out pretty good. We had a couple of hickups but ShareGate support was very prompt on helping us resolve the issues.

For Vault migration we used BitTitan as well and it was great both the product and support we recieved from the BitTitan team.

Let me know if you have any questions happy to help.