that article does answer some of my questions... it's pretty bright for an RPTV but eesh that's a pretty low contrast ratio.
you should be able to tell me what the viewing angle is just looking at the thing... does the picture get dim when viewing it from extreme angles? Roughly how wide an angle across the normal access can you go before the picture starts to lose it's brightness?
Honestly I'm disappointed you don't know these specs off the top of your head. You should have done so much research and cross comparisons with other TVs that they'd be ingrained in your skull, or at very least you knew where to find them quickly and easily.
It also tells me that you either didn't read my Display buying guide... or you did but didn't follow it

I usually avoid RPTVs as I find they only work well in dark rooms at eye level, looking at them head on. Anyway, as long as you're happy with it who the f*ck cares what I think

As for using HDMI instead of component it's a matter of native resolutions and not having to use the (in all likelihood crap-tastic) scaler built into the TV.
being that it's a native 1080p TV you might actually get a better picture if you go 1080i over component. usually a 1080i signal are clean and standardized enough that a translation from 1080i to 1080p can be done without artifacting. at 720p your TV is doing all of the scaling.. at 1080i your xbox is doing the scaling and your tv is doing de-interlacing, at 1080p over HDMI your xbox is doing all the scaling there is no interlacing involved and your TV doesn't have to perform any image manipulation (meaning the cleanest signal possible).