Hi @retypejonas
The save / load option will not only save the postmeta data, but will create connections from the post to the taxnomy term. This is to replicate the functionality of a taxonomy checkbox, like the post category metabox.
This however will not with with a user, only a post.
Nice work on the LIKE SQL, yes, this will be the only option for now and I’ll look into why the ID’s are saving as strings.
Thanks
E