Thee two watches are so totally different that I would hold off buying until you've figured out which complication you value most.
Aesthetically the IWC is a stunning watch, particularly with the silver dial and rose gold hands. You can dress it up with a black strap or dress it down with a cognac colored strap with contrasting stitching. The movement is a heavily modified ETA model that IWC transforms to a point where its origins are unrecognizable. The only down side to this watch is the lack of display back through which to see the movement. In my about-to-be-thinned collection this watch is a keeper
The JLC is aesthetically a "plain Jane" watch by comparison. Functionally it's terrific and I use mine for time zone shift travel almost every week. It can be dressed up or down very easily. It also has an in-house movement and a display back. In my about-to-be-thinned collection this watch will be going to a new owner...
So... figure out which complication appeals most and then spend an ungodly amount of time @ your dealer trying both watches on before you make the final decision