So what is your question?
Manufacturer SCOPs can be compared by looking at their datasheets.
Installations can be compared at HeatpumpMonitor.org
The primary factor that drives heatpump performance is flow temperature, which is in turn limited by the system design and operating settings. A well designed system will be able to run at a lower flow temperature and achieve good performance. A warmer house in a colder climate will need a higher flow temperature with reduced COP.
Trystan did some analysis of it here: