>Migrating contacts and calendars is easy, thanks to open standards (unless you're migrating in bulk)
Ehhhhh, Workspace has a half-assed EAS implementation that works until it doesn't (just had a client where it stopped exporting all his phone numbers, the data was still in Google but their EAS just wasn't outputting it). It's hardly an open standard but theoretically works for Outlook users migrating to Exchange.
Going anywhere else with an Outlook desktop user that actually follows the open standards (CardDav/CalDav) is extreme pain because Outlook lacks native support, so you need to use a plugin that will pull the data but not present it in the same way. The earlier mentioned client I moved to Fastmail and I still haven't figured out how to get his 'contact folders' to show and sync in Outlook without heavily customizing the views. Otherwise works in Android with DavX and iOS natively.
