My actual experience is that I origianlly had an analog cable hooked up to my Samsung and it looked great, but it was so ever not perfectly clear, even though you probably wouldn't notice upon using the machine. It is the text really. Switching to the DVI cable, though you wouldn't notice it right off, it fixed the ever so slight ghosting of the text to the point where it is perfect and no longer bothersome.
Though you may not notice it, it is way easier on the eyes. The other way could give you a slight headache without you even knowing it. The DVI however removes that issue.
My suggestion is - buy the cable and if you think it doesn't make any difference (unlikely), then take it back. I can almost bet that you will end up keeping it however.
No matter what is written above - there is 'always' a loss on conversion in any format. In this case you are converting from D to A and back to D. This wouldn't be an issue if you were staying A. So any noise generated in the analog line is going to be transfered back to D, leaving you with ever so slight ghosting that you can barely see or worse. On top of this, there is guaranteed to be 'some', but probably not enough to be noticeable, color loss. Its how electronics work. In a pure D to D environment, you get none of these issues.
Hopefully that explains it a bit better.
-S
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