I have the USB version. For the most part, I use it to watch television. I don't use the video capture features that much.
For television quality, its certainly fine as a secondary television. However, when I upgraded the drivers and the application that comes with it, there was a major decrease in the quality. I had to go back to the old versions for it to work right again. No idea why.
Personally, I think you can do better with the other products already suggested.