I'm not sure.. I don't know WS_FTP Pro, I've always hated WS_FTP
I used to have a nice script that synced complete webpages to another computer and produced differential archives daily. It could have been useful, apart from a few problems
It ran on linux/bash/lftp
It ran on a VPS account here at JodoHost that went "boom" (that was on VPS1 btw, shortly after VPS3 was introduced^^)