I have been really looking to buy a A T Pro or AT Gold. I live in Colorado and will probably be trying some creek detecting. I need to get some feed back from someone who owns ether of these machines, To find out 2 things. 1. do you have to have the AT Gold to find Gold and is the Gold really worth the extra money and 2. how long is the warranty on these as far as water proofing goes. has anybody had any issues with them quitting dew to water damage.