Move between shares with Rsync too slow, any alternatives?

Like to topic says:

I’m currently using rsync (via ssh) on a 5N to move files between a temporary share to a permanent archive share with rsync but this is excruciatingly slow (about 40 to 50 MB/s).

rsync -vrP ~/Shares/TempShare/ ~/Shares/PermShare/

I’ve read somewhere here in forum that this would be a better alternative than using Finder on a Mac, but I don’t find it much faster.From what I gather the files are being relayed by my Mac.
Am I doing something wrong?Is there a better (faster) alternative?

Ty in advance