Freeze is really meant to be a plain simple file transfer client, although it has some "helper features" like compare mode which shows differences between a vault's inventory and a local folder and the highlighting of duplicates.

But it is not meant to be a replacement for a full featured backup solution like Arq. I think some people like it a bit more "low-level" and simple and that's what Freeze is for.

> but de-dup and versions can't be done with the standard format

I really do not know.