I had the RD1s and the M8 upgraded x 3: SOLD THE M8. Sorry guys, I probably woke up on the wrong side of the bed today, but if you want a money pit, buy the M8. And sell me your RD1 for $500.
Re: prior posts: there is service for the RD1s, GOOD service support for a very reasonable price in Japan, as well as DAG/Steve's, etc.
Of note, many people diss the RD1s IQ based on the 6 MPs alone. I have had it explained to me that the size of each of the 6 million pixels was larger than your average size pixel in a sensor, so that the IQ was actually higher than a 6 MP sensor. I just did a Google search, and could not find data on this though. Higher ISOs on the RD1 are not as clean as CMOS sensors, but you will actually get some nice digital grain on the RD1.
All 4 of your main controls (SS, f, ISO, Exp comp) on the RD1s are at your finger tips, changed manually, rather than getting lost in submenus in the M8, and then missing the decisive moment b/c you were d*cking around with the crap-for-brains electronics of the M8. And the NOISE the M8 makes when taking pics is horrendous. Compared to the quite "click" of the RD1 shutter.
yes, the RD1 has drawbacks: the 2 GB card limit? buy a few of them for $8 each (yes, only $8 from a major brand): do you really need to take 100 pics of the same thing? If so, buy a dSLR. The limited memory will help focus on the image taking, like a film camera, and will redevelop your confidence in getting it right the first time.
I have never had focus or shutter problems with the RD1. In fact, the RD1 VF magnification is 1.0! much larger than the 0.72 on the M8. IOWs, higher focussing accuracy for 50mm+.
Thank you for allowing me to express my opinionated view.
Disclaimer: Despite my M8 bashing, I did by an M9. Ridiculous price? Of course it is! I just wanted something FF that would allow a 35 Lux to act like a 35 Lux, rather than a 50mm Lux (with 1.5 crop factor). I bought the M9 new with 2 year warranty, and extendable to 3 years, so I wont be pouring money into it, like I would if I bought a used M8 w/out warranty. E.g, you can buy an M8 used, out of warranty, have the sensor go bad, and then fork out ANOTHER $2k (in addition to the $2k you had bought it for) to fix the sensor. So then you are in $4k for the M8, which takes the short bus to school, when you could have just bought and RD1 for $1k in the first place.
In any case, good luck to you, and let us know what you decide!