Yes. You can always buy me a beer if you'd like.
There is no guarantee, because each add-on has their own developers and its own coding. This Add-On FULLY covers the default Concrete5 installed tables. If there will be (algorithm) changes in the future, this Add-On will be updated to cover the migration fully again.
The migration covers these “areas”:
However, if some tables are missing from the migration, the tool will inform you about that. These tables can be easily added to the custom script or migrated manually.
Also, ther’s a simple way included for each package to add more custom tables to be included in the migration. By writing just a few lines of code, you can easily include your site's custom tables to the migration. Please see the Documentation page for more information about this.
Could be, there's an Add-On for concrete5 5.6.x available with more or less the same options. This is named Database Case Sensitivity Migration (MySQL) - also a free Add-On. This one will not work on 5.7.x though, only with versions 5.4.2 — 18.104.22.168 of Concrete5.
I’ve gotten permission from the author of that Add-On, Antti Hukkanen, to port this Add-On to Concrete5 5.7, as he had no time to port it over yet due to (client) projects. This way, everyone can enjoy this Add-On already as much as we did back in the time – before 5.7!