A true dual-redundant regulator set-up only draws down from one pack at a time, usually the one with the highest voltage, leaving the other pack as back-up should it be needed.  This is different from a parallel connection that draws upon both packs simultaneously, or two packs connected to one regulator that does not discriminate/switch between them (based on available voltage).  There are certainly many options for Rx power so it will be interesting to see what others are using in their pattern ships.  Now that the season is here and practice days can be long and rewarding, I check both battery voltages before loading the plane into the car for the day, and sometimes again at the field if I am getting a lot of flights in.  Good habit!