Looking to pick up a 6" coil for a 505. I hunt alot of curb and sidewalk tear outs since that's my line of work. Unfortunately, theres alot of junk for my stock 9", and I like to have more separation. For the most part I'm looking for coins, but jewelry's a plus. Where I'm at in Northern Ohio my average ground balance is 5-14, so I think its safe to say its on the high side of mineralization. My question is do I go with the HF 6" or the MF 6". Any opinions welcome...Thanks.