Have been flying a mix of S and M modes using the FPV RC3.  Feeling was M mode significantly reduces flight time.  Today, flew all three batteries in M mode.  Made an effort to note flight times. Consistent 30% less in M mode with all three batteries.  7 minutes plus a few seconds is it.  

What are your flight times when flying the Neo in Manual Mode.  NOT the manual control on a smart phone.

Was considering just a 4th battery to charge loaded in the Neo while the others charge in the charging hub.  But now considering just purchasing another FlyMore Combo Kit and store the extra Neo as a replacement for when I trash Neo #1.  Net savings of ~$50 over eventually purchasing a replacement Neo. Otherwise it's +$150 for 3 batteries and the hub.

Good question. I’ll check. …

M should have more flight time for obvious reasons: 1) less computing power, since there's no assistance 2) it is not fighting the wind.

Stranno Posted at 11-2 13:03
M should have more flight time for obvious reasons: 1) less computing power, since there's no assistance 2) it is not fighting the wind.

M mode should have less flight time for the obvious.  Usually flying at a higher speed and steeper attack angles.  Both increasing drag, air resistance.  Higher speed with identical propellers requires higher motor RPM, results in more tip turbulence.   Tip turbulence reduces the relative efficiency requiring.  

S mode in the Neo is relatively slow.  IIRC, max speed is ~8m/sec.  Flying manual mode usually double digit meters/sec.  Watts(amp x volts), the power needed to increase speed is not linear.  It's exponential.  No hard data outside of flight times have been reduced in M mode.  

Starting to think it is not the mode, but the speed and skill that has significantly reduced the flight times in Manual mode v. S  mode.

Yesterday flew 3 batteries in Manual mode. Made an effort to fly steady, slower(6-11m/sec), no hard maneuvers.  Also, no crashing.  Flight times were similar to what I get flying S mode. ~10-11 minutes down to ~30% battery capacity.

Just from my experience with electric motors (R/C, outboard motor on the sailboat, backup chainsaw).  Higher demand (watts/min) results in exponential decrease in run times.