I have a Contax G1 and the R3A (recently purchased on RFF). My gf has several M lenses and I recently purchased the Summicron 40/2 (for the Leica CLE). I have the 45mm and the 28mm for the Contax. The contax glass is awesome, it matches the hype. The Leica glass also is great, and just using the lenses is really a pleasure.
I'm mainly using e100 and kr64. In the portra 160 kodak negative films, yes with the contax it sometimes feels too sharp or contrasty. With the slide films out of direct light, thats not really a problem. Each family of lenses has it's own character and performance issues in different light. So you need to settle on a film stock that exploits the sweet spots.
I'm not that experienced with manual rangefinder focus, so the biggest difference comes down to the rangefinder - what you see. The contax g has a tiny little hole to look through. This is weakest aspect of the camera. The bessa has a large viewfinder that is brighter and is 1.1 to what you see. It's wonderful. I've done side by sides with my gf's M6 and the M6 has a nicer 'pop' to the image but the size is better in the r3a.
The other big difference is autofocus. As you've read, it sometimes craps the bed with the contax g - you press the button and it can't find a focus point and the shutter doesn't fire. That will never happen with the R3A. At the end of the day, you probably miss the same number of shots - autofocus doesn't work versus you not focusing quick or accurately enough. In one case you blame the camera, the other case you get to blame you know who.
The other difference is the sound. The contax makes a very impressive frame advance sound "yes! you took a shot!", but the auto focusing sound is sort of a grinding terrible thing, especially if you are picking out a focus point and its going back and forth.
So yeah, both are probably near the peak of film camera design in their own ways. The contax G1 is probably a better deal and gets you shooting without much thought. I have the body, two lenses and the flash and I'm set. Hope it doesn't break. I'd certainly pay to get it fixed or buy a new body.
Once you go down the Bessa road, you open yourself up to some 60 years of lenses and viewfinders to choose from.