or have played with one I would like to hear your thoughts on what could have been done better.
1. A few more megapixels would've been nice, but not as essential as a full-frrame sensor. The crop factor is livable (I live with a 20D which is worse) but annoying. If nobody had a FF it would be different, but Canon does and it works really well. Yes it's a different horse being an SLR and there are special issues with the rangefinder lenses. But the M8 also costs twice as much as the 5D.
2. I can't comment on the noise at higher ISOs because I haven't checked for myself, but given the M Leica's pedigree as a low-light camera, I would have hoped it would be an industry leader in that respect.
3. A built-in adjustment for the eyepiece diopter would've seemed like a reasonable feature to expect in a $5000 camera.
4. Some way other than scrolling through a menu to change the ISO. On my 20D I have the LCD set to "off" (no review flashing under my eye) except when making the very occasional change to some parameter.
5. On the same note I would've liked to see some kind of opaque cover for the LCD, matching the vulcanite.
6. On that note, I was never thrilled with the slippery cover texture on my MP and wish the M8 had the nubbier cover from the M7.
7. A thumb rest where the advance lever used to be, as an aid to one-handed shooting.
8. Some way to fit AA batteries, even if it's an add-on to the bottom plate. The fact is I don't use my cameras much in-between trips but once in a while I want to grab it and go and don't have time to charge up a battery. It's also nice to know if you get caught short with all your spare batts depleted, you could grab a set of AA's from any local store and keep shooting at least until you could get to a plug for charging.
9. I don't see why they couldn't have kept a standard flash socket somewhere, even if not where it is traditionally on an M Leica. No longer being able to use a flash along with a clip-on viewfinder seems like an unncessary downgrade, like the botched redesign of the eyepiece on the MP.