The brightness or existence of the screen is a person preference.
That's why I said "I prefer" lol
I doubt you would find any measurable battery life decrease.
This is what i've been thinking, but again, it's a bright OLED screen vs a single LED, and at 10s or 15s X however many hits until empty, might prove to be more measurable than you think.
@OF I'd love to get your opinion on this as the forum battery pro!