I bought one as it was exceedingly cheap. It works pretty well. Unfortunately when I load up the software provided with it and activate the doobry, it knocks out my sound card, which then needs re-installing before it will work.
Other than that, pretty good value for money.
Here's some screens I've taken from
this video:


I couldn't get this video recorded on my DVD recorder as it kept jumping all the time despite playing perfectly. So that's a good thing.