MTP works ok with my rooted Xperia S however syncing music is a pain with banshee and others.

The solution?

Download an app called FTPServer. I use an FTP server instead of ssh because there will be less overhead because it is not encrypted. This is fine on my home network as it is just me.

Start the app, enter username, password, port number greater than 1024, the folder you want available (I chose just the music folder).
Then on your Linux machine, I use Linux Mint 16 with Nemo as the file manager so it might be different for you. Go to File, Connect to server, enter the details and connect Works pretty fast!

I will be using Banshee on the Linux machine as the music player. Download a Banshee extension called Folder Sync from the App store. In Banshee go to Tools Folder Sync. Choose the network FTP share as the destination. You can also tell it to make a playlist for you on the device and put music into the respective folders This is very handy. Press sync and the music will be synced to your device seamlessly! It is slower but much more reliable than MTP.

There is also a utility called curlftpfs which mounts an FTP share as a local disk drive which could be handy!

Hope this helps!