I tried out the drill with airsoft. With a single shot fired there shouldn't be much time difference between live fire and airsoft on this drill. Other modifications were that I lifted a 35lb plate instead of a 30lb backpack and was targeting a smaller 6 inch dot. If you're gonna do it, GO big!
Warmed up a bit before, working on both draws for time and accuracy at speed. Then ran about ten iterations. Decent exercise! Lifting the plate did slow my speed a bit, but could still hit 1.55 sec. Got some more practice to do to beat Garret.