A great little camera. Has a great viewfinder which does not flare, the rangefinder is extremely accurate, has easy film loading with a film window to see what film you have loaded, uses all the great Zeiss and Leica lenses, has aperture priority exposure with easy exposure compensation, the shutter curtains are vertically running metal blades which do not get holes burned in them. I mean, what is not too like?
In my opinion I can't think of much in the way of downsides. The rewind is on the bottom of the camera instead of the top. Not that big of a deal, you get used to it pretty quick. The shutter is not quite as quiet as the one on the Leica. This is true but the only one who can really tell is the guy holding the camera. If you are more then 2 feet away it is very, very hard to hear the shutter anyway. It is not quite as heavy as the Leica so for some it does not feel like it is built as solid. Personally I appreciate the fact that the camera is a bit lighter. The shutter is electronic and depends on batteries. This is true so if this bothers you then you probably don't want this camera. On the positive side, the electronic shutter is very accurate, more so than a mechanical one.
Buy one and enjoy it.
"One should really use the camera as though tomorrow you'd be stricken blind..."