I have just upgraded from my old type Milwaukee 1/2 impact to the high output 1/2 fuel 1400lbs breakout, I am super impressed, it will undo the wheel driver mounting bolts on a Cat 789, 1" bolt,1350 1400lbs, normally this requires a air impact 3/4 or sum times 1".
For the 1/2" drive and down, the electrics out now, will do the same work or more than as 1/2"air impact.
I have been looking at the New Milwaukee 3/4, its not that impressive 1500lbs, most quality air 3/4 are about that at 90 psi, 130psi they do much better.
The electric impact technology has moved up a lot in the last 3-4 years, I've got several older electrics, 1/2, and 3/4 Milwaukee that the new brushless fuel, walks all over.
Its nice not dragging a air line around, but a good electric and a couple 6amp batters arnt cheap either.