To be contrarian:
I fought with my goodman handle during training (yes roger) and after. Being left-handed. It is particularly difficult to illuminate a tie-off with a light on a goodman handle while manipulating a reel. Fighting with the goodman handle digging into my metacarpal despite our best efforts to glue a piece of neoprene over it made the experience that much less pleasant. I also found myself with my hand in an unnatural position while finning to keep the primary pointed where it needed to be which led to cramping.
I kept at it for another couple of months until I had the chance to borrow a razor soft glove/helmet system (that you linked) with the movable mount and that was super nice. Comfortable, etc, Wow, a light on your head makes task work much easier. It still took two hands to transfer the light from the glove to the helmet and back (maybe I didn't learn the trick)
I went to a helmet with mounted lights that I can turn on and off to illuminate a task and a 240g 21700 based primary light on a glove that still gives me 2.5 hours of tested runtime. What joy. I feel like my dexterity with the softglove is better then what I had with a cramped hand from the goodman handle. I went from 6000lumens down to 1400, but do you really need 6000lumens?
There is no easy way to clip the primary in the glove off one handed.