Have my Canon FF compatriots tried a Fuji X camera?

DFPanno,

Yes. I've got a 5d2 and also an X100. My motivation to get the X100 was similar to yours. I wanted a small camera for travel / taking everywhere (when I couldn't be bothered lugging the 5d2 and a bag full of lenses) and would not compromise on IQ. The x100 ticks all of these boxes. It is also very fun to shoot with. It is not perfect, but no camera is.

The jpgs are sweet, and can stand up to a bit of editing in post if necessary.

It is much more discreet than 5d2 for street (although I do enjoy using different lenses for street with the 5d2 also).

Some x100 samples if you want to check them out at link below - and for me they hold up to what I could get out of the 5d2 with 35mm lens. I don't think you would regeret getting one given what you've outlined in your criteria.

Went for the x100 rather than xpro as I didn't want another interchangeable lens camera, and also wanted the OVF. Good luck with your decision

http://www.flickr.com/photos/markforbes/sets/72157628848979557/

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Cheers, Forbaz
flickr.com/photos/markforbes