Speed/Torque Mode vs battery life

[Thomas Lippert]

I've owned a NanRobot D5+ for a month and like it!   Just wonder if anyone can give me some tips about the title subject.  I live in a hilly community - many 15° inclines.  My D5+ has the following choices:  Speed control has 3 options, ie:  Mode 1 limits speed to 12 mph, Mode 2 is 22 mpg,  Mode 3 is 35 mph.  Next I have Two 1000W motors.  Batter is a LiPo 52V 26ah.  I have a choice of using Dual or Single motors.  Lastly, Turbo vs ECO.  I use Mode 2 on the speed controller.  I find that while climbing a hill in Mode 2, Single Motor the speed drops to 14 mph.  I can easily sustain 22 mph if I use DUAL Motors.  I don't use TURBO because I think I'm conserving the battery.  Here's the question:  Which is better, ie:  Go up a hill in Single and feel the stain on one motor or use DUAL motors all the time?  In DUAL the D5+ has no strain and will easily climb hills without loss of speed.   With all the choices how do you ride your scoots?  I prefer using DUAL and  ECO.  I will use SINGLE and ECO if it's better for battery life.