Yeah, I would use it. According to the US Gear website, a "dual range" unit has the ability to go over and under drive, depending on the need, all from the controls.
Now, presuming that it is a complete unit, How much is it worth? I have already asked the seller about picking it up since I am only about 5 miles away from him, he is OK with that. So I can bid a little more than others since shipping is not a concern.
I also have a buddy that is an electronics whizbang (he even got me into IDIs), he should be able to make sense of the control unit.