Well, they don’t look that bad on their own - they just look waaaay worse than a decent bitrate file or even just a well-encoded low bitrate file - here’s a comparison of the 4GB version posted above with a well-encoded 5GB version someone (I forget who) made and posted on torrents with my blessing:
http://screenshotcomparison.com/comparison/169716
and here it is compared to my 7GB AVCHD version:
http://screenshotcomparison.com/comparison/169717
and here’s the 5GB vs 7GB (here, the difference is much smaller, of course, but the grain structure and fine detail is still better preserved in the 8GB version):