Is HDMI better than Component for Directv and HD?

I need help from people who own the Directv HD receiver box.
I own a true HDTV and I am in the process of purchasing a Directv H2O receiver and programming which also includes high definition channel capability.
It has composite, s-video, component, and HDMI video outputs.
I cannot decide which to purchase: component video cables or a HDMI cable for this receiver.
I have a few questions:
1. Between the HDMI and the component output, which has the best HD video quality overall with this receiver?
2. What about with standard definition broadcasts from Directv?
3. Are the differences in video quality between the HDMI and the component outputs big or small?
4. Are Directv high definition broadcasts as high a quality as the ones I can receive with my outside terrestial antenna?
All answers would be greatly appreciated.
I use both HDMI and component and I like them both, the main advantage of the HDMI is that it caries audio signal VS component and DVI which only caries video signal. There are few Satelite HD channels that are decent and the rest are crappy. I like the picture quality of the OTA better. The best HD broadcast that I ever watch was the superbowl.
the whole advantage of HDMI is that the signal stays digital and doesn't get converted to analog then reconverted back to digital, it's worth it
HDMI cable is clearly better with my 50 inch Sony SXRD. The picture has more detail and is more three dimensional. My wife noticed as soon as I switch cables. Now, it is not a night and day difference but it is easy to see in my case.
Thanks very much for your responses.
I will probably just go ahead and purchase both and try them both out since my tv has so many inputs on it anyway.
Thanks again!