I dont think so for the reason i stated. in my last post. In my limited knowlege (haha) in order for it to work you have to have a stable platform to put this on. that means the tank or torso. the tank does not follow the hands and arms. using a device like the compass function in the models you mentioned is one input the other is speed in that direction which can be obtained by motion speed sensors . with those 2 inputs you can get a relative position that will be what is called dead reckoning. perfect conditions no currents. Then with a program you can see the start and where you are in relation to the start point. whamo you can find your way back. Now you have 2 devices to keep water tight instead of one device on your arm. One device system on the arm will not work because the direction of motion is changed every time you reorient the sensor like moving your arm. I am sure there are systems out there because I do not follow the technology. However I do understand the problems with gettng a viable solution. Again if any one has some links to a device that does not rely on external transmitters, I would like to see them.The computers in that price range that I had in mind include the Perdix AI, G2, Suunto Core, Mares Genius and a few others. If they can add some communication/ navigation function it would compete with these.