The SuperDrive does what you expect it to do perfectly! You pop your disk in, it does it's business and then your done you can take the disk out. But...
I personal bought the SuperDrive with the newest iMac because of it's lack of built in optical drive. I thought to my self that I would NEED some sort of disk drive and that Apple had jumped the gun with removing the optical drive and going all digital media.
But after receiving the SuperDrive I have not used it once. On one hand it's a waste of £60 and on the other it shows that most types of media or programs simply don't require an install disk.
Also the USB wire is really too short! It comfortably sits below the USB ports but try and move it any further towards you and it's a no go.
The moral of the story is that only buy one if you have a specific requirement for it, for example you wish to BootCamp Windows 7 or you buy all of your films on DVD format.