P2C
That's interesting. Of course the hunts at KellyCo were not clad kid hunts, they were DEPTH hunts with various different types of targets, a bit of a different thing, one might think. Additionally the participants were WELL-seasoned detectorists who knew their detectors better than the back of their own hands, if you know what I mean.
I've seen but not done side-by-side tests, the E-Trac vs F-75 and couldn't tell much difference between the two for discrimination or depth but the E-Trac certainly is a decent detector. Sometimes the F-75 did best, sometimes the E-Trac did. However, the Explorers are I-N-F-E-R-I-O-R in depth compared to both the E-Trac AND F-75 and most people know that already. Even the lowly iron-loving Tejon beat the Explorers and Sovs for both depth and (especially) target separation - because I had one and it handed those Explorers and Sovereigns both a big, big can of whup-ash.
When it comes to the F-70 I admit that I know little about it except that the gain on the F-75 is substantially greater, and especially the LTD. In light soil the Garrett 2000 and 2500 and various Nautilus and Nexus animals and the Fisher 1270 go deepest of all, but how many people get that low-iron luxury soil anyway. The Fisher F-75's greatest virtue is that it does so extremely well in really high iron (magnetite/hematite) soils. Personally I find both of the F75 and eTrac to be inferior to the earlier single-freq 80's to 90's Tesoros and Compasses, etc as far as target separation, because I've matched them against each other and the various Minelabs really sucked. Sure the Tejon made more noise but it was superior to them.
Check this out:
http://metaldetectorreviews.net/detectors/211-1-fisherf70.html
http://metaldetectorreviews.net/detectors/209-1-minelabetrack.html
You pose an interesting question though, so I'm going to cruise the net and see if there is a video comparing the two.
Time for a big bowl of these navy beans and steak.
BTW, my main machine is an old Compass R&C and since I re-designed it and put it on steroids it beats everything BUT the Mighty Nexus, which matches it for depth but not in target separation and recovery speed, not in ten light years.
Thanks for the info and have a good 'un.
Larry