Hi Mick,
you say:
" I'm interested how the E-trac goes with the screw caps and gold coins." By this , I take it you mean Aussie $1 and $2 gold coins.
This is my interpretation thus far.
It's close to perfect. You'll dig less screw caps but initially you you should stay within recommended ranges and defaults if you want it to be closer to perfection and not fall into the "wrap this thing around a pole or tree " or "through it like a javelin gets thrown" category.
The E-trac does, within a depth range and a trashy environment , have a more rock solid digital number definition for the Au1 and 2 but can still not give a 100% definition, even though the pattern can be made tighter.
In an All Metal setting I used on a beach a while back, I dug a signal, one of sooo many( good and bad), that was down to about 12 inches. It was indicating that the target was beyond what the E-trac's depth gauge(another improved refinement for deep target definition) was showing.
I was expecting something substantial as it was a rock solid repeatable signal and was by all accounts, supposed to be a gold ring......turned out to be a VERY corroded almost indistinguishable, bar for those notched grouped line cuts on the sides of it, Aussie $2 coin.
My god, the salt, sand, time and whatever else had reduce this coin to almost nothing. What and encrustation it had!
To me , the E-trac is more stable and can be a "lap dog"-of-detector, but if you unleash it, you really need to be ready and expect to dig lot's of junk if you aren't prepared and maybe expect it to bite ya on the bum, like it did me and has done to others.
Just thought I'd mention, while I'm here, that I know Ray H. "pinpointa" had a try at the E-trac that he got to demo, but he's stuck to his xterra 70. "pinpointa" Ray H. is usually quite capable with detectors but reckons he was going to stick with what he has for now. I mention him because he seems to have the same criteria for coin hunting(mostly Au 1 and 2's) over the old aluminum bottle caps and felt that the X70 did it just perfectly. Personally, I haven't tried the X70 , so I wouldn't know.
Maybe hungry(bob) or Snowy or anyone else in Aus. using the E-trac might want to add or say more. You're all welcomed to.
Hope I've helped you with this answer.
David Di