I run copper all the time and love it. My most productive all season last year was the 300' (60 - 65' down). The 400' was a close second. I have 7 copper rods 100, 200, 250, 300, 350, 400 and a 500. It is a little expensive but they flat out produce. I would recommend starting with a 400 or 300 not a 600.