I hunt older home sites mainly. I use a Whites XL Pro. It has a discrimnate mode and all metal. I hunt in all metal mode on these sites. But with a flip of a trigger I can be in disc mode to further investigate a target plus it has a very accurate meter as another means of investigating a target. I use all this target info when I hunt, but many times just because of the sound from the all metal mode I dig. Sometimes it is just a beep or rise in my threshold that is repeatable,sometimes its a rusted square nail or other piece of small iron,sometimes like just the other day, a coin. I checked it in disc mode and didnt even get a signal. But I have to say, my meter bounced over into the dime range from one direction of swing, so I dug and found a 42 Merc dime.
I have to say also with the XL Pro, I hunt in all metal because of seperation speed. It is faster in all metal than disc because of the filters. But still, I like hunting in all metal at these sites.
I have a M6. It doesnt have the all metal mode and doesnt have a threshold. I use it for my tot lot hunting and some park hunting, mainly because it is a fast responder. But never have gained the confidence in it, like I have with the Pro. And, I think that is a very important thing, confidence and knowing your machine. Oh, I have found all the clad I care to with the M6.
Lately, Ive been thinking about a Tejon or Musky. But I have to admit, my crutch is that meter on the Pro.
Like I said, I think your confidence and familiarity with your equipment is important and I also am a firm beliver in different equipment for different types of hunting is important plus correct equipment matched to the envoronment/ground.
I havent used a lot of types/brands of detectors, what I have used, has been productive for what I mainly like to hunt,old home type sites where abundance of iron is burried and not much or any modern type trash, like tinfoil,pull tabs etc.
I dont post much here but reap the benefits from the more experienced MDers such as MichiganBadger and others and where and how they hunt doesnt match what or how I hunt always but they give accurate discriptions of the equipment they have used and how they used it.
I have to watch what some say as it seems they are biased toward on brand of detector and its not because they are actually biased but its because of whats worked for them in their hunt style and location, for example, I am using the Whites machine,it works for me, but thats not saying another one want work,I havent tried them all but am satisfied with what I have for now.
Good luck,
John