> Namely the Pros and Cons of the ZM compared to the MECHANICAL Leica.
This is an apples to oranges comparison, but you already knew that 😀
If you want a mechanical Leica, then nothing else will do. Get thee a mechanical Leica!
However, if you want a camera with AE functionality, then the ZI is an excellent choice. I don't buy the whole "when the battery dies, you cannot use your camera" argument, because its no hassle whatsoever to carry a spare set of batteries, and they're tiny and cheap so there's no excuse for not doing so.
As for build quality, sure the Leicas have a nice heft to them, but the ZI is very nice too. The ZI is noticably lighter than the Leicas I've owned (M3 and M6 TTL), and I suspect some equate that to be a less solid build. Personally, I think its just because the ZI is made of lighter, more modern materials, and in reality there's not a big difference between ZI and Leica build. But I'm not going to bang up my ZI to see if I'm right though 😛
The ZI's metal shutter is slightly louder (still not in SLR territory though) than the Leicas, but one thing I like because of this is that I can leave the lens cap off and not worry about the sun burning a hole in the shutter curtains. This advantage far outweighs the slightly noisier shutter IMO. Imagine being one month in to a three month trip and burning a hole in your shutter curtain 😱 Won't happen with the ZI 😉
Another advantage to the ZI is the ease of film loading. It's no contest! I can remove film and then reload the ZI much faster than on the M3 or M6 TTL. With the ZI there's no need to juggle a base plate, or flip a back door, or wish you had three hands 🙄
Regarding the finder, the M3 finder is the best I've used hands down. Amazing that Leica hasn't managed to top this in 50+ years since the camera was released. But I would rate the ZI above the M6 TTL by a fair margin. One of these days I hope to shoot with an M7 (with finder upgraded to MP level) or an MP to see if the finder is any better than the ZI, but its going to have to wait a while though considering that either camera would cost the equivalent of two or three ZI bodies 🙁
On the subject of rangefinder patch alignment on the ZI bodies, the first ZI I bought (used) was out of alignment when I bought it, and I could see it was out when looking it over before purchasing it. But I bought the camera anyway, and then took in on a two week trip to Australia as-is, with the intention of sending it in for realignment when I got home. It turned out that all the photos I took on the trip were perfectly in focus. No problems whatsoever. Although of course, the RF patch being slightly out was a little annoying. Anyway, I did send it in for realignment when I got home, and its been fine ever since. YMMV 🙂