Amal isn’t selling the copper style antenna implants anymore due to concerns that the overlapping wire will chafe and cause failures.
I have had mine for 3years with no issues… and I love it.
I got my first pcb flex just over 2 years ago and its still going strong.
Neither are in my wrist area though, but as a fair comparison, I have one of each in my P1 of my left and right hand,
In my opinion/ observations the PCB flex works well, but just not as well as my copper one, but the copper one is also larger and a…less smart chip.
To get you up to speed on some recent changes, the Resonant repeaters are a great new addition to the cyborg armament
Check out
RSP
and
They really are a huge improvement