Thanks mnem for your extensive description of your KSGER T12 soldering station!
I ordered a KSGER STM32 V2.1s T12 OLED controller. So no worries 'bout that..
As I wrote: I came across reports saying that this controller is sensitive to overvoltage.
When I have my controller I will check what it is and what it's capable of.
The tip of the T12 cartridges being actually fully isolated would make ESD compatible design of T12 soldering station easy!
Too late for me, I took the steep way...
The DC buck converter you used would have been enough me, too.
Anyway, my DC/DC converter is capable of delivering 4,5A continuously and 7,5A for a short time.
I expect short heat up times and good/fast heating when soldering.
I would have bought this one for 80€ pesos
https://www.ebay-kleinanzeigen.de/s-anzeige/loetstation-oki-metcal-ps-800/1525324912-168-1929
I've soldered with different Weller soldering stations throughout the years and found them to be very good at their job.
Currently I have two WECP-20 and a EC 2002 "antistatic".
I noticed that I have three of them because changing the tip is a pita. These three soldering station eat up valuable space, their cords interfere with each other and I happen to use only one station regularly.
I've come to a point where it's clear to me that only for having it a little more easy to change top another tip by firing up the next station has come to an end.
The T12-based soldering station have caught my attention long ago; For me the T12 cartrigde with integrated heater (better/faster heat delivery to the tip) have the advantage of being able to be changed quickly by just unplugging and plugging. If one uses a silicone heat insulation pad it's possible even with hot tip -unlike the Weller with its srewed mechanism (pun intended).
After all that's been said about the Metcals I might consider them, too. -if one should come cheap one day.