As a recently returned rsync.net customer, I was a bit surprised to peruse the docs and see that Fuse/sshfs is still up as a recommended option for Mac integration (see https://www.rsync.net/resources/howto/mac_sshfs.html). A few months ago this led me down the path of trying ExpanDrive/StrongSync, but this is the first I've heard of Mountain Duck (love Cyberduck though). I'm looking forward to giving it a spin now but if it has been working well for you please consider updating this page for others. Happy customer otherwise!