I've used and do use an older White's Bullseye, a Merlin, a Sunray DX-1 on my MXT, and the Treasure mate. They all do a pretty fair job of what pinpointer is supposed to do, but I like the Sunray and the Treasure mate the best. The reason is they both have a noticeably better reach, just enough that to me they are a bit more useful. The Treasure Mate takes a bit of fussing to tune it, but is very sensitive to small metal and as it's not connected to the main detector like the Sunray, you can use it with any detector. On the other hand, I've had to go back and retrieve it a time or two when I'd forget to pick it up which can never happen with the Sunray on the MXT. Some post they never use a pinpointer, but I find that most of the time they speed up my recovery when the object is small, especially if it has taken on the color of the soil and also when the target is just inside the wall of the hole where you can't check it with the coil on the main detector. Just recently I did a quick hunt on a wood chip tot lot where the chips just under the surface were very wet. I found 15 pennies about half of which I would have had the devil of a time finding as the wet chips matched the older pennies in color very closely. The really shiny ones weren't much of a problem and the quarter and nickel I detected showed up very well, but boy, those older pennies were darn near invisible. As to the Treasure Mate warranty, I've haven't had to use it so can't offer much there.
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