I've been using it for a couple of years with Google Drive on Windows, on a near-daily basis, with approximately 300GB across multiple vaults - some very large files, some very small text files (think Obsidian).
I have not encountered any errors / issues / lost data. I do frequently get a message where it tells me it can't lock the vault because it's still "in use", but I just Force Lock and go on with my day.
I second this. Using it with Pcloud. Syncs just fine, and even if it does not fully sync from one computer, I haven't had it corrupt while using the files.
It's the super very best of the best. Beside encryption it also uploads stuff faster than shit like folder sync pro. Never has any errors. One of my most favorite open source apps, love it so much I even paid for the supporter certificate. (And I don't pay for lots of free stuff cuz I'm poor). If they would allow single folder sync on android it would also be much better than nextcloud.