It will certainly make finding it very easy if dropped in the water in the dark though. The LED is bright enough to blind you. We use it as a flashlight at night when we have the dinghy someplace - very handy for seeing the combo lock on the dinghy and navigating dark trails and beaches.
The GPS nav abilities can't compete with a proper GPS for sure, but the proper GPS's can't compete with the ability to send waypoints back to the mothership in real time or maintain communications with a single device. For us out cruising, exploring, diving and spearfishing, this little device is a gem.
If we had the chance to get the older model for $100 less, we would have jumped on it also.
Mark