I'm contemplating this controller (or rather, 2 of them) in my new house, and am looking for good and bad experiences with this controller, even from installers. I am especially interested in some more esoteric experience with the controller: Using the Groundfos flow meter; configuring the external relay to power two pumps, one with a 5 minute relay for a high head drainback tank; you know, stuff like that. I will probably use the Heliodyne panels as well, but not the heat exchange appliance, as you can probably tell. Anyone? Thanks in advance, Jeff