Yes there is a difference. Some of the 1.3 cables are 25' long, but are only certified for 1.5'. It has to do with the bandwidth the cable can pass across its entire length. Some cables have built in amps, some are passive, some use copper conductors some use silver plated copper (silver is a better conductor), etc. Not all cables are created equal, you will start noticing this easier as bluray players are becoming higher and higher bitrate for a wider range of colors and black level detail.