I agree with charliek. I have both the Freedom and III lights, and prefer the Freedom over the III.
First, it makes a lot of sense to be able to ramp from dim to bright from the Off setting, which the Freedom does. The III goes from only bright to dim (which the Freedom can also do it that is prefered). Second, I find the single button easier to use than trying to get the right position for the front or rear button on the III.
A bonus is that the LED can be changed in the Freedom, so the color can be changed at will (don't know about the III).