I am in the beginning stages of replacing my old conventional heat pump with a geothermal system. I have decided to purchase a WaterFurnace system. I lean towards the 7 series even though my contractor thinks the 5 series would be sufficient. Our home is log, 1350 sq. ft. with a full finished basement, very well insulated, and easy to heat. The unit we're replacing is a 2.5 ton heat pump with a 3 ton evaporator. I'm liking the 7 series over the 5 series mainly because I understand the 7 series to be an inverter system. and I'm told the 7 series uses EEV technology. My question is about the controls. My installer recommends a series 5 with the basic controls. I like the tech of the Symphony system for the monitoring, precise tuning, and troubleshooting. The off site (WiFi) stuff is something I'm not all that jacked up about, but that's part of the package. Also, do you know anything about the AXB advanced controls ?