Don't Cosina build the Zeiss Ikon, they certainly build most of their RF lenses. I have an M2 plus a Bessa R and a R4A with a lot of CV lenses. A Bessa won't come close to the quality feel of any Leica, but that said, they are a lot cheaper and (in my experience) work just as well. The problem with Leica is the astronomical price for their lenses, very hard to justify when the CV lenses perform so well. My most used outfits are the M2 with a 35mm Nokton and the R4A with a 28mm Ultron and 21mm Color-Skopar. The R4A is a bit plastiky but so far has been reliable, the viewfinder/rangefinder combination is excellent, as is the metering.
If both outfits were similar prices then the Leica would be a no brainer, but they are not and you need to weigh up how much you use the camera and how hard. The Cosina and Leica will produce almost identical results but the Leica will last longer and have a much better resale value..oh, and that red dot!