Thanks pinkpanda.
Some weeks ago I modified the X40. Just a basic mod. Stock emitters was too CW for my taste (cooler compared to 1A, and the stock CW emitters in the TK75 as an example) The emitters also had that extra bit of red/pink color in them so I considered them good for de-doming. You can actually notice that in the beamshot if you compare to the TK75. I was not a huge fan of the stock emitters.
Here is a quick peek under the skirt of the X40.
Fairly thick aluminium reflector.
Nicely attached copper mcpcb (probably DTP based on the limited sag, I did not test). I forgot measuring amps at the emitter.
The screws that were holding the driver in place had zero epoxy or anything on them. So in my light it was effortless to get the driver out. (I think Acebeam now makes it much more difficult in all their lights.) R082 and R100 looks like sense resistors. I did not play with them. Light is not regulated when voltage becomes too low, its only got 3 cells, I want to use high capacity cells, and Im not that tempted to resistor mod these lights that got fancy electronics for the charging circuit and such. So I left it stock. Got more pictures if anyone likes to see.
De-domed emitters.
Stock O-ring below the lens was a PITA to get nicely in place on my light since it should have been a bit wider.
For some reason I experienced an issue with sometimes activating strobe when setting the light on highest setting. I tried to make sure that the driver was twisted in a way that made sure the strobe was as far as far way from the magnetic field from the highest output setting as possible, but I still experienced that strobe got activated in some cases. Fixed that with drilling up the driver screw holes with a 0,5mm larger drill bit. That meant I could twist the driver 0,25mm further away. Problem solved! I recommenced to not take out the driver if you don't have plans on trying to modify it. Zero issues with accidental strobe activation in the past weeks.
Numbers:
X40 80190cd (2913 Lumen)
X40 de-domed 151200cd (2625 Lumen)
That is about 90% increase in cd and 10% loss in lumen according to my lux meter. Tint became NW. No red in it anymore, its got a little bit of the typical de-domed tint (with hints of more yellow/green), but not much. It turned out decent. Which is pretty much as good as it gets for de-domed XM-L2s.
I have also measured new (stock) RC40 that I just got in.
RC40 134190cd (3591 Lumen)
All numbers can be compared in the bonus section in OP.