I think there are lens for the C3 as well but a pain to change. Looking at the manual the C4, and 44 have an integrated rangefinder, body made out of metal, self cocking shutter. I sorta of like the separate rangefinder, like the Leica screw mounts the magnification makes for a precise focus. Don't like the squinty viewfinder. I guess I'll take the plunge and get one.