OK I've done a quick test today, please note I'm no FF2 expert and the reason for me doing this was to see if I could enjoy the experience better by reducing the draw resistance.
The thinnest disks I could get were 0.5 mm Stainless which are thicker than the supplied screen in the FF2.
All tests done with latest Firmware, temp set at 205c with the calibration set to 110%, with mouth piece screen in place, medium grind, not packed etc
I tested the following 1 mm holes out, draw resistance very easy, no charring, but FF2 overheated after one bowl.
So I tried the screen with the 0.2 mm holes (pic below) and the draw restriction felt much better, easy now compared to the original screen and not a huge difference when comapred to the 1mm holes as above, I got more even colour in the AVB when compared to the standard screen too.
Original on the left and my 0.2 mm holes on the right, I'm happy with the FF2 now.
I got a few of the 0.2 mm screens if anyone wants one but I can't post anything on the classifieds due to me being a new member of FC.
Hope this is of use to some