Glance: Always on vs peek

[ishaan_666]

Which of the 2 settings drain less battery?
while always on would mean the display is always kept awake, on the other hand, peek implies the proximity sensor is continuously busy.

Also, is says in settings double tap to wake takes more power, but is the effect on battery life too high?

 

[montsa007]

I think, turning all of the 3 off will give you optimum battery, guessing from the features they offer.