I have found the FX-888D not up to what I require.
It's made of thin flimsy plastic and as a result bends and flexes too easily when used and doesn't stand much wear and tear.
All the plastic and metal parts have been made too thin, saves a few cents.
Have used it at home, at work in the lab. Tried it on a production line as the sales rep insisted it was ok
, found the same problems in less than a week.
I have the older FX-888 version (with a potentiometer for temp control), if I'm not mistaken the FX-888D is identical except the front panel and control circuit ; they have the same chassis, same iron, holder etc.
I also have a KSGER "T12 soldering station" version 2.1S in extruded aluminium case that I bought on Aliexpress.
I'm not in a production environment and don't know the specifics of Kerlin's requirements, but as a hobbyist, in my opinion it is actually quite the contrary. The FX888 iron and station have been very reliable for me over the years. The T12 station has nowhere near the same build quality, its PSU is junk with safety issues which have to be addressed as soon as you buy it, and the iron itself is crap made of brittle plastic.
"Cartridge" technology VS "traditional heater + separate tip" has been discussed many times here, I highly recommend you dig a little bit with your favorite search engine. Obviously there are better irons than the classic FX888D, but I actually don't think a T12 clone is one of them. Just my 2 cents !