After researching the OKM EXP 4000 and some of the other products they carry, I still cant come to a conclusion on if I want to purchase th exp or something may be more "reliable" such as the minelab 4500. Im searching in areas with lots of minerals and not that much trash. Im lookin in depths of 10-30 ft deep, and looking for larger sized treasures. Im not really doubting the capability of each of the machines I just want to make sure the okm is reliable. or should I just spend less money for something thats not as advanced but works better?