The best beach is one where tourist go to the beach wearing a lot of jewelry and carrying a lot of change and go back to the motel with no jewelry or money. Haven't found that place myself yet though.
Seriously, I have found most beaches to be about the same. There's a lot of crape - bottle tops, pop tops, crushed cans, sinkers, fish hooks, crushed beer cans, nails, parts off boats, galvanized things, etc. and not much good stuff. There is always change and the occasional ring, bracelet, etc. The mix is different on different days and different beaches.
Most beaches that have tourist also have several to many people who metal detect the beach on a regular basis. The beaches in Georgia and South Carolina I detect, have at least 2-3 other people detecting at most any time of the day.
So my advice, since a beach is a beach is a beach, is to get the best beach machine you can afford and learn how to use it as best you can. That means a good test bed and practice, practice, practice. If you have an old sandbox nearby, use it for testing and wet it down with some Instant Ocean from the pet store. Just out hunt the old retired guys (oops did I just dis myself) and the guys with the Harbor Freight machines.
Now if you are going to surf hunt, that is a different bird.
Daryl