I checked out another one.. Amana AH093E35AXAA
Amana AH093E35AXAA 9200 BTU Air Conditioner Heat Pump - eBay (item 390292223049 end time Apr-25-11 12:49:31 PDT)
Ebay dealer sent me this:
The unit will switch to electric heat somewhere around 32 to 38 degrees F. Because it switches to electric heat, there is not a point where the heat pump is at 50%. I hope this helps.
- super_six_two