I did a lot of research on heat pumps when I was having my pool built and I decided on the Aquacal line. I went with the mid sized Heatwave Icebreaker (reverse cycle mode) for my pool and so far it has worked like a charm. They have an extensive line of heat pumps at various price points and have an excellent warrenty. The heat pump (and pool) have been operational since last November and have kep me swiiming and/or in my spa all winter in N. FL.
Scroll compresser and Titanium exchanger also in the Heatwave models.