Yeah, don't buy premium DVI or HDMI cables. In most cases they are a complete waste of money.
You've got to figure if they can send a digital signal with about 100 channels through 100 miles of air from the transmitter to your aerial (Freeview) or 1000 channels (including HD channels) from a satellite through about 500 miles of air (Sky Digital) to your satellite dish, and get perfect reception 99.9% of the time, that it's no problem to send one signal down a 2 metre highly conductive copper cable from your PC to your monitor, or from your DVD player to your HDTV.
My £7.99 HDMI cable works perfectly.