I use a White's DFX and have used it for 13 yrs now. Well, in 13 yrs, many improvements have been made in detectors and maybe I should look into a change....I'll think about it.
My back-up is a Tesoro DeLeon.....quite a powerful detector. It was a used yr old (New=$600) and I got it for $300 shipped. A good thing is that the Tesoro also uses (8) AA batteries as the DFX.
Thanks for the posting of the Minnesota's Place Names book info L C B....the info amazed me. I'm going to buy the book....it appears to have a tremendous amount of info in it.