I made the switch a few months back. Manually migrated my files over using the desktop apps for both, but it was maybe 200GB of junk so it didn’t take long.

OpenCloud is great. Much faster, much simpler, does what it needs to do. That being said, it is very new so documentation is lacking, and the desktop and mobile app are VERY basic (the mobile app doesn’t have a dark theme and only offers a limited photo sync right now, for example, instead of setting various one or two-way synced folders).

It’s also worth nothing that their compose file and OIDC support are both a mess. The compose file is easy enough to work around, plenty of folks have put together cleaner, minimal single file setups. For OIDC, I did get it working with Authentik but it loves to constantly log me out mid-session in Librewolf all the time. For some reason they use a hard-coded clientID for OIDC, and even worse the ID is different for web, desktop, and mobile. Very bizarre.

So it’s far from flawless, but it’s early in development and overall it’s still a better fit for me than Nextcloud.