The X-Terra 70 is a great machine. The versatility of this detector is what makes it. It is one of the best coil/relic machines on the market, yet is still a very capable gold finder. The X-Terra will find small gold that the PI machines will miss. It will not go as deep on the nuggets as a PI machine, but still does a very respectable job. For the person who wants a detector that does it all, it can't be beat. The learning curve is quick and the verity of coils available in different frequencies and sizes allows it to do a lot of things very well. For the money, you won't find a better machine. I have a Minelab PI detector and for finding the deeper nuggets in the well worked fields, it's the best choice. The problem is that that is pretty much all it is good for. I love my 70 and think it was the best money I have spent on a detector. The weight of it is another major factor. At less than 3 pounds, you can swing it all day. My PI machine gets my less than perfect back hurting pretty quick.
Buy one, you won't look back.
Good hunting, John K