You should leave auto-sync enabled. There's no difference here between a manual sync with auto-sync enabled and disabled, so there's no reason to disable it.
This may be a unique-user question so (if you think it wise) feel free to delete this post.
I use Zotero in 2 ways: 1) the standard way, as a reference manager for academic writing with LibreOffice and 2) as a tool to import records from Open access databases such as PubMed and from journal publishers' websites, edit the imported records, immediately export those edited records in MODS format (to be imported to my online database) and immediately delete those exported records and empty the Zotero trash.
I keep auto-sync off because my thrashing import/export/delete process of records I'll never use in my writing seems to be pointless. (Why sync records that will only live in my local and online library for a few minutes?)
I do need to remember to manually sync when I add records that should have permanency for me personally.
Should I not be concerned about syncing the temporary records as wasted server traffic on your end? I'm adding and trashing 400-500 records every day.
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I use Zotero in 2 ways: 1) the standard way, as a reference manager for academic writing with LibreOffice and 2) as a tool to import records from Open access databases such as PubMed and from journal publishers' websites, edit the imported records, immediately export those edited records in MODS format (to be imported to my online database) and immediately delete those exported records and empty the Zotero trash.
I keep auto-sync off because my thrashing import/export/delete process of records I'll never use in my writing seems to be pointless. (Why sync records that will only live in my local and online library for a few minutes?)
I do need to remember to manually sync when I add records that should have permanency for me personally.
Should I not be concerned about syncing the temporary records as wasted server traffic on your end? I'm adding and trashing 400-500 records every day.