Thought i'd add my 2c worth. I started off using a bessa r2 when it first came out and then migrated on to leicas, having used the m7, m6ttl, m3, m2. I am currently using the konica hexar rf so i think i can safely say i have gone full circle. Of the lot, i think the bessas are great cameras for the price. If u spend most of your time shooting out in the streets, no one will hear the shutter cos of all the background noise. I expect the r2a, r3a to be at least as good. The vibrations are also not a question under such circumstance, since shutter speed is probably high.
The leicas are great in that respect, while they are not silent (go get a p&s digital to hear silent), they come close. The best part is that the shutter movement is very well dampened so that there is little or no vibration. I have a few 20x30 on my wall taken at 1/2second exposures to prove. Useful for travelling when tripods are not an option. Also great for indoor stuff, shooting in clubs, etc where a shutter's flick will spoil the mood.
Then there is the konica, which has not been mentioned so far. I think of it as a compromise. I got mine new with lens and flash for 2k, so a used one should be 1k or less. Its not the most silent in the world but its shutter is well dampened. The motor drive makes more noise though. I love it simply because i have the functions and features of a r2a, with a motor winder and the good dampening comparable to a leica.
Cameras are all a compromise. Take note that a used m6ttl and earlier cam will probably require a CLA soon, which can set u back another 200-300USD.
