Ok I looked at the site... here's what I got from it.
Is it going to give you "near s-video quality" like it says? Probably not.
Will it improve the quality of your display?
Believe it or not the answer is yes. The fact that it keeps the signal in svid format until it reaches the end of the cable is going to cut down on signal degredation dramatically. It will also help color bleeding a little. Your overall sharpness in picture might or might not be affected.
Is the price right?
Yes again, only 16.99 for the standard cable. (The rest of them are overpriced btw and kinda the same thing with audio out tacked on, which you don't need.) Your going to pay about 10-20 bucks for a decent svid cable so that's pretty good.
Should you try it?
I don't think it's a big enough investment to have to worry about the loss of money. I might pick one up to play with myself.
I hope that helps out some.