Sorry guys. Been swamped with work and can finally give a review of the 507 and my impressions so far.
I've had about 15 hours logged on so far, probably 4 or 5 have been critical viewing via Toshiba XA2 HD DVD player.
There are many different parameters across various menus. This set is a tweaker's delight no doubt. That many settings caused a couple hiccups for me, but REWARDS patience and trial and error.
Initially upon HDMI hookup, my Toshiba XA2 looked merely GOOD with HD DVD's and OK with SD DVD's. After several minutes, something wasn't right, which especially bothered me with HD DVD's because I'm used to seeing them sharp as a tack. This worried me as I am VERY picky about PQ and called the industrial sales rep thanks to Chris at Cleveland Plasma. Mike instantly had suggestions, and KNOWS THIS LINE OF PLASMAS BACKWARDS, as he owns the 507 himself.
The rez problem was because I had not properly signal formatted the panel and the SD and HD DVD signals were being TRIPLE processed! Once by the Reon chip in the XA2, then by the Key Digital card and then by the panel. The result was a soft picture that I was not impressed by. I was on 750p and selected the 1280x720 ATI signal and IMMEDIATELY noticed a dramatic difference in sharpness with all signals routed through the Key card. Now we're cooking with crisco!