Nope. You can use SSL per user or for SFTP. You can access a mapped drive via https using a users SSL cert, you don't need SFTP running to do so. That is why I said SSL. And that is why I asked for opinion for most secure. A person has to have CIFS setup on local network to access that drive via internet. So yes, that is the same.
I have a webpage that I use both SFTP and/or https webdisk to access. It can be accessed by either SSL type connection.