X20 vs X100s @23mm
Fuji XE-1 Check
Fuji 18-55 2.8-4 Check
Question(s) of the week:
Given the rather large initial price difference between the X100S and the X20, other than the APS-C sensor, does the X100S have any significant low-light/speed advantage over the X20?
In addition, does the X100S have any (presumed) advantage over the forthcoming Fuji 23mm F1.4?
One or the other will be purchased as a back-up for the XE-1 and used primarily street shooting.
I'm having some difficulty understanding your question since you seem to have answered it yourself. Perhaps you can rephrase your question if the following isn't what you are expecting....
The APS-C sensor size is a HUGE advantage as well as the superior light gathering ability of the X100s resulting is cleaner pictures and the ability to crop your photos should that be necessary and maintain quality to some extent. Prime lenses generally perform better across the frame than zooms, but you'll need to refer to the lens test results when they become available. If these things aren't that important to you, than its not worth the "large initial price difference".
There is the difference in DOF and the ability to isolate the subject as well.
Its really difficult to say with certainty anything about a lens that hasn't been made available to the public. The 23 f/1.4 could be a real dud, OTOH it could be as magical as the 35 f/1.4. About the only thing that can be said at this point in time, is "its a stop faster, will have shallower DOF and in terms of performance...unknown".
R3A M7 M9 X-Pro1 E-M5 X100 DP2