High quality HDMI cables make for quality video and audio. A beautiful TV and nice sound system may be the most obvious parts of your entertainment system. But don't trust your system to cheap cables.
If you are running HDMI cables in the wall you need FT4 certified in-wall rated HDMI cables to meet fire or building code. It's important that these cables be cUL or CSA rated for Canada. Cables from other countries are not normally acceptable by Canadian authorities.