What exactly do the compression numbers mean? I would think 5:1 would mean that the file is compressed to 1/5 its size but the three numbers confuse me (4:1:1).
Anyways, I finally got an opportunity to get the screencaps from the vhs and Hi8 sources.

VHS 2nd generation

http://www.uploadfile.info/uploads/ae3b83509b.jpg

[url=http://www.uploadfile.info][/url]

Hi8 1st generation, s-video cable used

http://www.uploadfile.info/uploads/a7197ff1c0.jpg

[url=http://www.uploadfile.info][/url]

VHS

http://www.uploadfile.info/uploads/4b819458e4.jpg

[url=http://www.uploadfile.info][/url]

Hi8

http://www.uploadfile.info/uploads/54353146b3.jpg

[url=http://www.uploadfile.info][/url]

Basically, the vhs screens appear more 3 dimensional to me while the Hi8 screens look more washed out and flat. In the second set, the trees in the background may be sharper from the Hi8 but they stand out more in the vhs. I also like how the sky is not as overexposed from the vhs. Based on how that field looks to my eyes at the same time of the year (late October), the grass is too bright in the Hi8 screen again.
While the vhs appears to be smooth and as clear as possible from the tape, I see a lot of either small dots or noise within the Hi8 picture.
It's easier to spot on what should be solid colors. I can see it at half size too so I don't think it's due to interlaced picture. I highlighted the best examples. This is from my 8mm but I used a Hi8 camera with s-video for playback.

http://www.uploadfile.info/uploads/64bf7012de.jpg

[url=http://www.uploadfile.info][/url]

Look very closely at Link and Zelda's faces.

http://www.uploadfile.info/uploads/5f7deb5684.jpg

[url=http://www.uploadfile.info][/url]