The problems described above also apply in connection with my Oregon 450. This means that the holder does not lock because the clip for having the wrong shape. Furthermore, you have to remove the GPS device in order to read it. This problem must not be forcibly regarded as Fehlkonstrucktion, but it's more of a general problem of the mounting rail on the unit. If the clip the other way around as often desired, the device would dangle upside down on the holder. Then there would be a risk that the device disengages from the bracket. Law of gravity just ...
Overall, I attach the mount only a small benefit in that it will retain, however.