I'll ask again:
Do the M7's have a history of electrical problems?
How inaccurate are the M6's shutter speeds?
Yes, but... If you get a newer M7 or one with the fixes, they seem to be very reliable. The major problems of the M7 as far as I can tell were threefold:
- unsealed viewfinder eye piece - dust can get in
- pre-MP style viewfinder that flares
- electrical DX reader
Most cameras have the first fixed, a lot have the second (after serial number 2885xxx I think), and some have the third. I think getting the third fixed is free, maybe even after warranty.
The third one is the big electrical problem. The cameras have a tough time reading the DX codes sometimes. Also film can be tough to get out of the camera. Get one with the optical DX reader and you should be fine - I've had zero problems with mine.
There are some isolated reports of other problems, but this kind of stuff can happen with any camera. Including MPs.
As far as inaccurate shutters, I think the word is that at higher shutter speeds, all mechanical Ms can get off, and I think a lot of them are off by about a 1/3rd of a stop if I remember correctly. In most situations, you have nothing to worry about. If it gets off, send it in to get adjusted. The word on the street is that the M7 should be better with this because the timings are electronically controlled, so those values shouldn't drift like they can in a fully mechanical system. Of course, I don't really know; this is just from what I've read on the internet
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