Hi Ian,
Yes, flip to all-metal and ground balance, the same as you would any other Tesoro. I use the all-metal to pinpoint occasionally, but only on targets that I suspect to be too big to be a coin. I ran across an area on my last couple of hunts that had a lot of what appeared to be melted
steel chunks. They registered a 95, but looked a little fishy on the graph. I could have gone to the SUM mode, or just flip to all metal and see how big the chunks were. I did a little of both. The nice thing about all-metal on the Cortes is that the ID still works. I'm sure it probably does on the Deleon too, but I don't know for sure.
I didn't buy mine new, I saved about $150 on a slightly used one. It had some problems, but Tesoro fixed it up as good (or better maybe) than new, at no charge. On the subject of pricing, my opinion is that pretty much all the detectors are over-priced. When you can buy a pretty powerful laptop computer brand new for $700, it's hard to imagine why a single purpose machine, with a fraction of the electronics costs the same or more. Electronics have been getting cheaper for the last 30 years or so in every area is seems except metal detectors. I know that there is research and development that goes on, but how often do you see new, revolutionary machines? Okay, forget revolutionary, how about just new machines? Tesoros' "new" machines are a good 5 years old now. Other industries have R&D too, but that doesn't jack up the price of the product beyond what is reasonable. I'm afraid that the Chinese will probably make serious inroads into this market too, because they will (are) pricing their machines more realistically.
Having said all that, I will still spend the money because I love metal detecting. But if there is a bargain to be found, I will take it, as will others too from what I see.
Dan