I bought one from my internet dealer for $680 for 60-months, supposedly bumper to bumper.
When the details of the warranty arrived in a few days, I quickly cancelled it since it did not cover basic elements like the center pod electronics, DVD navigation, audio system and heated seats and many more.
Murano anyway has 60 months warranty on the drive train and if the electronics are not covered, which are more likely to go wrong than engine and other mechanical components, why would I need one ?
Please make sure any extended warranties cover items like NAV, heated seats etc.