OK I have both!!
Well I had an X-T1, now have an X-T2 and have the 23mmF1.4 and I have an X100F
Some points (in a random order)
1) The XF23mm F1.4 is as sharp at F2 as the X100 23mm lens is anywhere
2) X-Trans3 sensors (X-T2, X100F) are sharper than X-Trans2 (X-T1)
3) I thought the extra resolution of the X100F would make the X100 23mm lens a real weak point, but it doesn't, as the sensor is sharper, its actually made the best of the lens, but the X100 23mm lens is still soft especially to the corners at F2
4) The X100F is a much smaller and lighter package than X-T1(2)+ 23mm F1.4. Its just a lovely handling camera (the only initial issue is the position of the Q button, but you soon get used to it.
5) You can't shoot at F1.4 on an X100 camera (obvious, but worth pointing out!!). If you like the F1.4 DOF then you won't get it with the X100F
6) The High ISO capability of X-Trans3 is much better than previous X-Trans sensors, although specification wise its only slightly better the way the noise manifests itself, means that it can easily be cleaned up. I regularly shoot up to ISO6400 (and even 12800) on X-Trans3. I could only dream of that on X-T1. So if you shoot in low light the better High ISO noise management of the X-Trans3 negates the reason to shoot at F1.4
7) You get ACROS with X-Trans3, this has different high ISO noise characteristics again (much more film like), so if you like B&W photography, this is lovely to have. It also is very good when shooting colour as if set on the EVF really displays the tones in the image well.
If I had to have one camera I'd keep the X100F, its just fantastic and the image quality sublime.
Hope that helps (oh and at £850 the X100F is a bit of a bargain, your only decision is the colour black or silver??)
