HD PVR 2 GE, worth it, thoughts?
There are a plethora of capture cards on the market in that general price range from numerous manufacturers.  There are two main things to worry about with these devices.  

First, for analog inputs, such as component video, you need to consider the quality of the analog to digital converters as well as what capabilities they have for scaling and format.  Not all converters can handle arbitrary analog resolutions (or digital for that matter).  You want the highest quality converters to digital you can get for the resolution you need.  For SD feeds, that may actually mean getting an older, cheaper device that has good converters, but doesn't support HD (and doesn't need as advanced of a hardware encoder.)

Second, once you have a digital signal, the quality of the hardware encoder matters greatly.  HD video is very, very large in raw data, so heavy compression has to be applied to store it and make it playable.  This compression is generally a complex and time-consuming process, but specialized hardware can allow for real-time encoding that can keep up with a live feed.  The quality of the encoder will directly impact the quality and size of the end video.

As far as comparing between one device and another, looking for reviews or video samples from each is probably your best bet.  As there are many devices out there, you are unlikely to find people who have used both and can compare them directly for you.  You might have more luck with finding people with first hand experience of popular devices like Matrox's MXO2 or BlackMagic Design's Intensity, but those are (slightly) more expensive professional devices.