Thank you everyone for you responses. :-)
[PizzaDad]
I believe you are correct that the camber is to keep the bar from sliding off your back. Because the safety squat bar has those handles the posterior delts are not forming a shelf for the bar to sit on. So altering the bar is not a good option.
[Jonathon Sullivan] "With practice, you can get pretty close to low bar mechanics." Jonathon, What do you alter in the movement so the lifter can bend over without pitching forward? They do fairly well until the weight gets to about 50% of body weight.
[Fulcrum] I like those squat handles. I think they show promise!