(Diehard, I hope it is OK to link to that page. If not, let me know and I'll edit out the link)
You can do anything with the site as you see fit, its there for people to use.
If you look at Epic's version of the texture, you can see that the general colour balance on the S3TC version is significantly different from that of the original. Even worse, the added detail in the texture really emphasises the repetition of the pattern over a large surface (like, say, a floor).
And, you have no idea how difficult that is, accidentelly i have been working on those textures last night, all evening. And i concluded that the new texture i am creating might emphasise it even slightly more :/ . There is little you can do about it, other than reducing the contrast, which will ruin the detailed looks. And the more detail, the more paterns can be ephasised unfortunatelly. Effectivelly you have to make it more bored and uninteresting to get rid of the repeat, which kinda counters the effect S3TC tries to achieve.
If for some reason S3TC are not enabled (or can not be displayed) the low-res version is displayed. So yes - it will work in UED.
Yep, i forgot to mentin that, though there are people that also achived in getting the full S3TC to work in UEd. And as sidenote, i do disadvise using the UTRP textures for editing, since its to much uncharted territory.
It's still unclear to me whenever it is true S3TC or not, but result is still damn good .
I still doubt that too, but it would mean that they are added uncompressed full 24bit. Which means the quality is higher than S3TC, but it also means that the effectiveness S3TC has, lacks here. So its quality versus compression/effectiveness.
ASIDE: Diehard, which NASA site are you getting the very high resolution images from? The last time I went looking for some images (admittedly, of Jupiter and from an earlier probe), I couldn't even find 1024x1024 images.
I have to dig for that, but each half year i go look for higher resolution stuff, but sometimes the most obvious things are difficult to find. Theres several NASA/ESA related sites that offer super duper high resolution files (300/800 Mb files) but for planets you gotta look very hard. Up to this day after several years of searching i never found the moon larger than 1024(if it was that large) :/
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