Minelab doesn't really have any real competition in this area so they dictate prices. Is the Explorer SE worth $1200?
$3500 for a GP3500 is worth it to serious gold hunters in AZ, Nevada and Alaska as nothing out there touches it in the depth department. PI gold hunters are always looking for more depth as you can go back to old patches and dig deeper gold with deeper machines. You have to be SERIOUS and a regular gold hunter in those states. They can make up the cost with gold found but of course it is not easy and a lot of hard work is involved. Some serious relic hunters use them too. Should be some good used prices on the GP3500 shortly as Minelab's GPX 4000 just came out. $4000 for a new GPX 4000(A bit deeper they say).
So it depends on the level of your addiction.
George
Excal 1000, Excal II, Sovereign GT, CZ-20, Tiger Shark, Tejon, GTI 1500, Surfmaster Pulse, CZ6a, DFX, AT PRO, Fisher 1235, Surf PI Pro, 1280-X, many more because I enjoy learning them. New Garrett Ca
I try to use the one that best suits the type of hunting I am going to do that day. That is why I use more than one detector. Some are better than others and the price usually shows it as far a quality of components, quality control, tech support, and service after the sale, unlike the cheaper discount detectors.
The adage, "You get what you pay for," holds true.