Interesting comparisons, and thanks for posting them.
I really liked the F100, but I did find it rather heavy to lug around if I was walking a city centre for an entire day; it took terrific photographs, and was a wonderful - and forgiving - camera, but physically - I did feel its weight after a while.
Re the M6, - leaving aside the Summilux lenses, (I have two, the 35mm and the 50mm, which are a pleasure to use), I love the weight, the size, the solidity, and the ergonomics; the thing is a pleasure to hold. It also sits - extremely comfortably - around my neck, and is very nicely balanced.
When my F100 was feloniously removed from my suitcase after several delayed flights, and a very delayed return of my suitcase - en route back after leave while I was working abroad some years ago, I had a choice of going digital or going retro, as I had always wanted to try out Leica.
Anyway, I went the retro route, deciding to defer any sort of switch to digital, as - at the time, digital SLRs were monstrous door-stopppers, and I didn't know the first thing about them, and - not least - the standard of picture taken by digital cameras still fell quite a bit short of what a good film camera could do.
So, - after some time - I bought a M6 and have slowly added a few lenses, enjoying the whole process.
The irony is that time expands as well as contracts. While I have some stunning lenses - and they are superb for low light - and also can obtain very good quality film (the rubbish that was so readily available 20 years ago has all but disappeared and the only film available nowadays is more or less of professional standard), it is becoming an increasing challenge 1) to find places which will develop the film for me, and 2) to manage to get that done in less than a week.
I won't say that it makes me nostalgic for the old 'One-Hour' photo turnarounds - I never availed of them, but to be able to develop film in a time of faster than a week would sometimes be rather nice.
