This may not be a useful comment at all. I should also add that I don't have or use any digital cameras, least of all an M8. I also don't own any M film bodies. But here goes.
There are two reasons I will stay with film for the time being. The first is that I love the simplicity of all my cameras. I set the aperture. I set the shutter speed. I focus. I take the picture. That's all. No need to worry about jpg or raw compression, colour profiles, image sizes, white balance on top of the normal photographic settings. (yes, you can set these things and stop worrying, but I would feel unsure whether or not the settings were ideal for just this particular picture and I would end up fiddling with them)
Until recently, therefore, I used to say that if someone made a digital camera, ideally small like a rangefinder, with only the basic settings, I would buy that camera and go digital. I guess (not speaking from experience) the RD-1 and M8 come close. However, and this is my second issue, I next realised that I really don't want to spend hours on a computer to get the most out of my images. (and yes, I guess you can automate it to some extent - but I would feel guilty not using all of the bells and whistles that I could use)
Re-reading my own message, it sounds more like I have some serious hangups about wanting to fiddle with settings than that my objections are anything photographic 😀 . Nah - 🙄 as long as the missus is happy living with my foibles, who cares, right?
Good luck with your decision!
Doctor Zero