When I hunt, unless I am cleaning up a tot lot, I usually knock out iron and leave the rest.
If I am looking for targets in that low range, I have a Compadre for that, and those tot lots, but from time to time I do turn the iron back on while using the F2.
The only decent thing I have found with the F2 in iron so far is a very small clasp on a very thin chain in a tot lot.
Came in as a solid 06, so now I turn on iron and dig a few of the more solid, steady low numbers in sites that don't have tons of iron trash, which is rare.
There is a possibility small gold can come in at iron and I would hate to miss that, but I usually hunt most of my sites more than once, and I am lucky enough to own more than one detector and the Compadre works better for me in that low end.
Also, the 3 top tones sound pleasant to me, that low tone bothers me.
Maybe because I don't hear it as much I am just not used to it.
I have done a search and can't find the exact numbers where these segments split, which is strange, you would think Fisher or someone else would have posted a list somewhere out there.
I will keep looking.
I just sent an E-Mail to Fisher Labs about this.
Maybe we can get a correct answer from them soon.