Back years ago when all I lived for was dredgin, I thought I would try my hand at some detectin. I went out and bought a Whites GM4. At that point it was the newest vlf model that whites had produced. Just like Rob said, I got nothing but frustration. I messed with it for about a month or so and then it went in the closet. Very rarely after that did it come out in several years. I just did way better at the end of a dredge nozzle and none of my buds were interested in electronic prospecting at that point. After the BS cali dredge ban, I decided to give beepin another go. After the GM, I knew I wanted a pulse machine. Whites had recently come out with the TDI and it was more affordable than the newer minelabs. So I went that route. I used the TDI for a few years, honed my skills a bit and found some decent gold. But the TDI just didnt have the depth and sesitivity I needed. I finally decided to take the Minelab plunge, and boy am I glad I did. I found a used 4800 and with half cash and half gold I purchased it. Right off the bat I was finding gold in places I had already hit hard with the TDI. I have been using it for about a year and have done well. In my mind there is no substitute. The GPX gives me confidence that every time I go out I have the best equipment available for finding those deep targets and the shallower ones that a vlf or even the tdi couldnt. Well worth the investment. Minelab GPX's are bad to the bone!!