I have one and love it, I have modified the bracket and mounted it 50mm higher so the tailgate goes up a little higher. It will still rest on the arm though but it hasn't given me any problems yet and i've had it on 2yrs.
Also be wary of the one you are looking at as the listing is using Rhino Roof Racks pic but you are not buying a "foxwing" it will be a copy. I sell them and they cost me a heap more that that rrp $799.