Jim, here's the pics of my two beauties. The Bronica RF645 looks only a bit smaller than the Mamiya 6, but feels alot smaller when you handle it. I can not stress enough how nice the RF645 is to handle. All the controls are in the perfect place and the metering is better than either of the Mamiya's. So why do I have a Mamiya 6 you might ask? Firstly because it's square! Square is not for everyone, but I personally love the square format. Secondly, the lens can be retracted (as you can see in the one pic), a very nice feature when hiking or when you need to fit the camera into smaller spaces (The Mamiya 7 or 7II doesn't have this feature). Thirdly, I do like the Mamaiya 6's shutter better than the RF645, it's a simple "click." The Bronica makes a weird moaning sound (which is actually the shutter re-cocking). And lastly, I believe that the Mamiya glass may be a bit better overall than the Bronica glass, but this is nit-picking.
If I could only own one of these cameras, it would be the RF645, but I would want to have another camera for 6x6. The controls, metering, and overall feel of the Bronica RF645 are just fantastic! Both are great cameras and you can't go wrong either way.
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