For clarification, b/c someone on another forum asked, I tested the systems graphics to the fullest of my abilities and found the following out:
Ok, here's what I've found out testing between my LCD 16:9, and my older sony 4:3 XBR (HD CRT circa 2002)-
1) even in 4:3 on the LCD (a Samsung 5265), which I have to "force" it into, btw, the resolution is listed as 720x480 and looks fine. At 16:9 it fills my screen with no stretching notable, which makes sense as the native resolution is still listed as 720x480 (still widescreen/barely HD).
2) running the component through a receiver with HDMI output into my Samsung and using the feature known as "JustScan", which is a wonderful feature that displays the native signal I get 720x480 15hz/60hz, fills my screen. Notable at extreme right/left viewing angles (which isn't good for a LCD anyway) are vertical lines of some dark color, which when viewing properly from the front aren't there. Maybe it's just my brand of TV, dunno.
3) Running on the Sony in 4:3 out of the component everything filled the screen, vibrant colors, but it couldn't tell me anything regarding the resolution. (I just wanted to check it out since I had it out, previously only having plugged up the composite to verify it all works).
4) I rechecked the sound slider, the UniBIOS v2.0, ran all 3 of the games I am giving away with the system, and tested the stereo channels to verify both function.
5) Did not test S-Video, but honestly, between Composite and Component.
Now, I dunno if the native resolution for SNK titles was 720 or not, but my LCD is pretty thorough, heck, I can even adjust color channels through the HDMI (which, unlike many HDMI TV's, it'll accept sound through). 720 is what it's showing, but there's no way it was 1080i or 1080p. I did not think to try and force upscaling with any other device. And yes, I can get 1080p via component.
Hope this helps answer a question. Sadly I'm not the most technical person beyond being able to hook all this stuff up, and knowing the difference between 480i/p, 720p, 1080i/p.