Few Factors to be considered and can actually be determined by knowing the drill(s) very well.
A)
2 of those are newer with plenty more torque (*Hammer Drill Handle is attached to Drill with Longer 'C' like clamps)
1 drill has a hammer drill handle attachment is only 1/2" gripped onto the drill, older drill and less torque.
B)
They don't show the batteries:
5ah xc is basic and can do the job for an entire day.
6ah xc is basic with a little long day run time.
6ah HO "High Output" upto 50% more power out to the drill (Milwaukee Drills Specialty)
9ah HD "High Demand" longer day use but not the 50% power boost
C)
Different Thickness of ICE where each Drill is stationed as only the people shifted and not the drills.
I'm a big believer in the StrikeMaster Lite Flite, but I did notice not same drills in the video.
Cheers,