Actually, this is something that bugs me with the SV/SL models: while using a heat pump is very efficient, it makes a single point of failure for all climate control... I could live with a broken A/C in the car, but I couldn't for heating. Have users in this forum reported issues with their heat pump vs the resistive heating system in the past?
There have been a few heat pump failures, but it is usually the much simpler resistance heater that fails, oddly enough. It's especially common in the 2013 Leaf. Oh, and before 2013 there is no heat pump: the heat comes from an energy-sucking liquid-transfer system that doesn't even have an off switch. There is a separate A/C unit. The S also lacks a heat pump, but has a much better air-heating unit that is shared with the other models as the secondary heater.