DVI is better than VGA, all else being equal. However, I've never heard of a 25 ft DVI cable for use with a computer. Unless it's the highest quality imaginable (i.e. 30+ dollars per foot) I have a hard time believing that it's not going to suffer a serious loss of bandwidth over such a distance.
Ideally, you want video cable's to be as short as possible. And a short VGA cable might be better visual quality than an overly long DVI cable, depending upon environmental factors.
How's that for a non-answer answer?
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