My son will be turning 6 next month and has asked for a metal detector. He goes with me on short trips and is pretty good finding finding things. I have a Prizim V and he cues in on the sound and then looks at the display. He is very good with it at the beach, but also good at home in the Virginia clay. Because of his age, should I go with a kids Bounty Hunter Treasure tracker Metal Detectors or something like a Prizim II or III. The main concerns I have are the size of the unit, weight, and complexity.