For years I have been using off camera flash, no matter what camera I happened to own at the time. It produces beautiful lighting when done properly and helps you avoid that flat, “deer in the headlights” look with your images. David Hobby (Strobist), Zack Arias and Joe McNally (just to name a few) use off camera lighting all of the time (I know, I’ve seen them in action) and if you want to improve your flash photography, I recommend you do too.
I find myself using my X-Pro1 all of the time (and soon, the upcoming X-E1) and I have continued to use off camera flash. I had an unfortunate incident with my old Pocket Wizards (which were extremely reliable) which I used to trigger my remote speedlights and wanted to replace them – ideally with something smaller to match the compact size of the X-Pro1.