I hate to say how many detectors I have in various configurations . . . . . the Sovereign with the WOT or even the Excelerator coil gets amazing depth on the beaches of SC where I tend to hunt more often. With the amount of ferrous trash from Hugo in 1989, it makes using a PI very challenging unless you want a full workout.
On the other hand, I have found that a PI detector on the south Florida beaches has given me an edge over my CZ-20 or Excal. But there are some great hunters in those areas that make great finds with them. The PI's are a tad more sensitive to the small stuff but once you get into rings, the edge is harder is distinguish
Heck, on fresh water sites, the Tiger Shark is unstoppable when it comes to charms and chains . . . some of which the CZ & Excal will not hit even when the target touches the coil.
Again, if there were one detector that did it all, my wife for one would be a lot happier . . . . . use what works for you in your area and for your style of hunting,
Andy