[Hey Bill, Im surprised your unit can make heat down to those cold of temps with no assist from the auxillary, that makes my above post inaccurate. Sounds like theyve come a long way in technology since I purchased mine 7 or 8 years ago. We bought a Carrier which was one of the better models you could get at the time
Yeah, I didn't believe the HVAC contractor before our heat pump was installed, but it has worked beyond my expectations. This is what I have without the solar option: http://www.lennox.com/products/heat-pumps/XP21/
For years I had heard about heat pumps blowing cool air and taking forever when the temperature was in the low 20s and below and it was why we never owned a heat pump previously, but have been pleasantly surprised. All of our previous homes were all electric and heated with an electric furnace which were effective at any temperature, very reliable, but expensive to run.
Bill