Yes, if you have your Xbox in middle of nowhere and you don't want ugly wires.Mine is behind the monitor, so I don't even see it when I play games, so I'm fine with cable. :D
How do you put the discs in?
If I'm not mistaken you can save games from the disks onto the hard drive, so he might not need to.
You still have to put the disc in to play it. It's just so the loading times are a lot faster and the thing makes less noise. Really pointless imo.
I think you can hook up external hard drives through the USB slots though.