I have a Bessa R2C, and believe that it is a fine camera. It feels solid, handles well, and I have never had a problem with it functioning in any kind of weather, even several hours in below-freezing temperatures. The Copal shutter is a little loud, but has the reputation of great reliability. I really like the ergonomics of the camera, but that is because I am predominantly an SLR shooter, and the placement of the shutter speed dial, wind lever and shutter release are very much like a modern Japanese SLR. The accessory side-mounted grip is very useful too, because it is easier to hang onto one-handed. Also, the Bessa has two big advantages over a classic Contax- the lever wind and the switchable 35/50/85 framelines. I don't remember the respective weights offhand, but the Bessa is a bit lighter, if somewhat less compact, than a Contax IIa. The internal meter works quite well, although I must say that I don't use it much, preferring to use a hand-held meter with RFs. The onboard meter does allow a primitive form of auto exposure, but again, I don't use it much in that mode. I have used the R2C sucessfully with a wide variety of Contax lenses, except for the pre-war 35 Biogon and its Russian copy. I don't know if the Bessa will mount the pre-war Biogon (the distance to shutter issue), because I don't own such a lens (yet). The R2C has a shorter rangefinder base that either the pre-war or post-war Contax cameras, but I have found that it is only an issue with the Bessa when trying to focus a 135mm lens. The Bessa focuses the 85/2 Sonnar without any problem. If I want to use the 135mm lens, I find that the Contax II or IIa are much better. All in all, the R2C is a great camera.
That said, I usually end up using either a Contax II or IIa, mostly because I like the idea of getting great results from a camera that is older than I am.