Epson R-D1

Opinion: I have had this camera since 2006 and it's now 2011 and I'm still using it several times a week. That has got to speak for itself, especially when you consider I have the Kodak FF DSLR the SLR/n, Canon 1DsMkII, Nikon D1H, 50D, 20D, 450Xsi and 300D and Olympus E-P1 and Pannasonic G1.
The 6mp provides excellent IQ and at a smaller file size. When using my Leica 50mm f/1.4 Summilux First Version the IQ is as good as that from my 1DsMkII. The R-D1 is a real all mechanical camera that happens to have a digital sensor and reversing/closable LCD screen. It's a pleasure to use and the shutter cocking lever is exactly like a 35mm film cameras. It provides me with a good rythem for my work flow. All the mechanical controls are external for everything, it's the only camera I know of that is like this.
I used this camera without flash with the Summilux at f/1.4 this past Thanksgiving and the images were better than those from my 1DsMkII with 580EX flash and off camera flas bracket and a whole lot smaller and lighter to use. I was using the R-D1 in very dark conditions at ISO 1600 and slow shutter speeds as low as 1/39 sec and many at 1/45 sec. But because there is no mirror to flip up and then flip down there is very little vibration so the shots came out sharp.
The viewfinder works very well for me and focusing is one of the most enjoyable things about this camera. The all manual focusing is very exacting and this improves the sharpness and image detail over other cameras.
It also takes all of my 9 Leica lenses, which are very small and portable.
The smallish size of the R-D1 makes it the most portable of all my better digital cameras save the Oly E-P1 and rhe difference between these two cameras in size and weight is not all that great.
If I were someone reading this I would search around untill I found one of these excellent cameras and purchase it. Even if it takes 2 years to locate one. That's my advice.

Opinion: Great camera with Leica lens compatibility !!

Opinion: This is the kind of camera which is very difficult to review.

Bad:
For someone used to Leica, the rangefinder is difficult to use. With a Nokton 1.8, getting an accurate setting for the distance at 1.8 is almost impossible. Lines in the viewfinder are difficult to see at 28mm. Battery life is poor (compared to DSLR), even with the screen turned off.
Vignetting is usually quite strong and requires corrections for all my lenses (Nokton 50, Konica 20, Voigtlander 12)

Average:
The resolution (6Mp) of the sensor is quite good, but not amazing by today (2006) standards. It is what it is: a D70 sensor...

Good:
Because of the size of the sensor, the results are excellent regarding noise at high sensitivity. I recommend using Pixmantec RawShooter over Epson PhotoRaw: noise reduction is much better. You can end up with very good shots even at 1600 ISO. Shooting raw is in my opinion mandatory. No compact cameras, even today, can reach such results.

Bottom line:
The camera is too expensive.

Opinion: I been using this camera extensively for the past 2 months and I am very hppy with the whole experience. It is my first rangefinder camera ever, so it took me a little to get used to it, but once I did, my images are far superior to everything I have achieve with my D70 even when they share the same sensor. The tonal range is wider, and the files simply don't look digital. The camera is a joy to use and gave me back the pleasure of actually taking photos... I don't feel like a tourist anymore! I suggest using RAW mode, I do it all the time, and with the new firmware upgrade you can save RAW and JPG atthe same time.

Opinion: I been using this camera extensively for the past 2 months and I am very hppy with the whole experience. It is my first rangefinder camera ever, so it took me a little to get used to it, but once I did, my images are far superior to everything I have achieve with my D70 even when they share the same sensor. The tonal range is wider, and the files simply don't look digital. The camera is a joy to use and gave me back the pleasure of actually taking photos... I don't feel like a tourist anymore!

Opinion: As has been said by others: beautiful, solid feeling, indeed gives you a completely other photographing experience than say, a Canon. I use it a lot in low light stage-situations with the Noctilux 50/1 and the results are very, very satisfying, the difference with other digital camera-results being noticable for everybody. I also took it with me on a holiday trip thru southern Spain, using it as a regular 'tourist' camera and that worked also extremely well (also with Summicron 35/2). Of course all dusk/dawn-photo's stand out because of the Noctilux, but the quality of the digital innards is very un-digital. For me this is the ultimate 'toy', or should I say 'instrument' to carry around as much as possible: it has a tendency of turning middle-of-the-road takes into something more artistic-looking and by and by you become a better photographer which means 'writing with light' (at least the illusion is there...).
Value for money: this is a subjective concept and should be treated as such: if you love this 'thing' and appreciate it's uniquenes - in contrast with almost every(digital)thing around you - the price is almost exactly right. ($ 2500 would be more realistic maybe).

Opinion: Excellent camera, M-like, top results with Leica/CV/Zeiss lenses. Cannot substitute a
DSLR because of 0,7m limit and only 28-35-50 lenses can be used. All other wideangle
show vignetting and need special 1,5 finders which are quite difficult to obtain. Beside
of that a real pleasure to use.Rangefinder not as precise as Leicas (shorter base) and
Noctilux delivers random results at full aperture (!with Epson 75mm 1.0).Price is now
down and imho almost correct (2300usd range for boby only).

Opinion: The camera is great and a lot fun to use, yes you can probably get similar quality on a cheaper EOS 20D if you use top quality L primes, however if you like to use your Leica lenses, and enjoy shooting with a RF camera, you won't be disappointed.

Opinion: a very fine piece and makes you go back to the "slow-photography" to enjoy.

what i cant understand that someone wrote "but the quality could not be detected over the quality of a Sigma 18 to 125mm zoom lens on a Digital SLR", well that guy must be blind or has no clue how to use the rd-1. sorry, to say that, but comparing any leica lens on the rd-1 to the quality of a sigma lens with 18 - 125 zoom? come on guy get real.