help choosing a new detector

One of the best simple machines for iron trash is the Vaquero. It may be the best machine for big pennies I have ever used...finding many below the plow zone in trash. Lifetime warranty $500 with a small coil that you will need... I can almost guarantee you will keep it in the arsenal no matter what you upgrade to.

Tesoro makes a nice machine.

I agree on the big coppers, my buddy with a Cibola has 5 Canadian large cents for the year, one of which he just found a few hours ago.
All of which were found in city parks.