You could download it with ClipGrab! Works very well for me, it's how I got the music tracks I then assembled together. It just downloads the videos as they're stored on the servers, so you're seeing the same level of quality - no re-encoding involved.
This is a good example of what I'm meaning.
Although there is an entire sub-section dedicated to this, so go have a look to get a good example of what I'm talking about here.
http://www.amazon.com/Best-Sellers-Kindle-Store-Humorous-Erotica/zgbs/digital-text/7620220011#1