In reply to Robert Durran:
I have recently changed to a Panasonic GM5 with the small 12-32 mm zoom for use on multi-pitch routes. It is a fairly unusual camera from a few years ago which I guess didn't sell very well. It has the same 16 MB Micro Four Thirds sensor as the much better selling GX7 from the same time. It weighs 10 oz with lens, battery and card, and is small enough to fit into a pouch made for (large) compact cameras and hang from my harness.
I can see the argument for staying within the Fuji system if you are already used to that and have lenses, accessories, etc. However, if you don't mind jumping systems, then I can recommend looking at this one.