Having recently got hold of a HDTV and Xbox360, I was keen to wire up my old Xbox through YPbPr as well to see if it made any difference. Although skeptical about output splitters, I went ahead and bought one of these with fingers crossed. All I can say is "excellent". There is no quality loss with any product going through this product as far as I can tell; my X360 still looks gorgeous!
If you have more than one HD product and want both plugged in at the same time (with only a switch to flick for your required input), you could do an awful lot worse than buy one of these. Excellent value for money, excellent product.