I wanted to use this tool for backing up my laptop to my NAS, however it only allows SSH to be used for data transfer, which is a real bottleneck for speed. It basically means you can only transfer as fast as one core can decrypt or encrypt data on either end of the pipe.

I ended up using https://github.com/oetiker/znapzend instead, because it can use mbuffer for the actual data transfer, which is much faster.