Synergy is not at all difficult to use or set up under windows.
My primary rig is a windows machine due to me playing a lot of games and I wanted to experiment in trying to make the rest of my daily tasks being done on a linux box.
Rather than having many keyboards and mice lying about I tried different solutions, the first being a headless box which I could connect through VNC and have remote desktop access, as due to being a noob I am not totally comfortable with the CLI.
Next I tried Synergy, this was the answer to my dreams, no lag compared to using vnc and real easy to set up even for a new user like me. My only issue was, when I rebooted my router as it is my DHCP Server would lose connection but I solved this by reserving an address on my router rather than applying static IP on pcs themselves.
Now , it just works and I'm sooooo Happy!! ;))