Hi Bill
That would be the TDI Pro PI machine IMHO. It is great machine with a good warranty, and great company backing it up. I can do a lot of things well and is the best over all PI for the price. If take the time to learn it and know it's little tricks, you will have one of the best detectors out there. It very good with EMI and will handle any ground in 99 and 44/100 in world. It is about 90% of the performance of the big high priced PI's and about 1/3 the price. It is not like a VLF so you need to clear your mind and learn the TDI for what it is, I spent close to 200 hr of field time with mine before I really got the hang of it, so nothing is free, you will need to put in the time. I don't give performance numbers be cause there are just to many variables. I can say that if you get the coil over gold and all conditions and setups are right you will be digging the yellow stuff on regular bases. I will work good on deep old silver that VLF will never find and it can handle trashy parks and beaches very well.
Keeper Swinging
CH