I have an old Tif, 11 yrs old and still works great. I don't know if new technology has improved on anything. Also have used an ultra sonic detector with good results.
"War is cruelty,and you cannot refine it." Sherman to the leadership of Atlanta prior to burning the city.
"Common sense is the collection of prejudices acquired by age eighteen."
"Another means of silently lessening the inequality of property is to exempt all from taxation below a certain point, and to tax the higher portions of property in geometrical progression as they rise." --Thomas Jefferson to J. Madison, 1785.