I always recommend Pre Pot external pro sound.
So the new jack gives you a clean, line level out with reduced noise floor and expanded dynamic range. You have no control of that volume at the device - must have control at mixer/preamp.
Then you still have the choice to use the headphone jack for headphones and the volume controls the speaker and headphone as normal.
Headphones won't work properly through the pro sound jack because there is no headphone amplifier in place.