I have one and consider it invaluable...
It basically shows you all the parts from any year Audi or VW (not sure if it includes 2001s). It lists the parts and associated part numbers and makes things extremely easy when ordering parts from the dealer or from clairparts.com. It also can come in handy to see how the parts fit together.
I paid $25 for mine, but think its worth $250!
Now for the bad...
- You must be running your display at a high resolution.
- Somewhat difficult to install if you don't know the tricks
- Make sure you get the US version so all the part numbers will be correct (I actually have 2, the first one I got was the European version)
- You are not going to get a real CD, just a burned copy
- I am sure that this is illegal