I just side-graded from the M262 to M10. There are some pros and cons.
Both ergonomics and haptics on the M10 are significantly improved over the M262. The body is the same size as my M7, although it is slightly heavier. The controls are well placed, and while the ISO dial is difficult to use one-handed, it works much better than the plastic disks used on film cameras. The shutter sound is quite different - slightly quieter, and less annoying than the M262’s clonk, but still noisier than the M7.
As a glasses wearer, I do not find a significant improvement with the viewfinder. The eye relief before was practically zero, so presumably a 50% improvement is still practically zero. For me, the 35mm framelines are pretty much the entire field of view - exactly the same as with the M7 (0.72x viewfinder).
There are some downsides. There is no aperture information saved in the image files, even through the camera has an estimate. The battery life is also worse (budget for 1.5x as many batteries as for the M240/262), and oddly there is no image-review-while-shutter-held option - one of my favourite features on the M262.
The main upside, other than haptics, is the excellent and fast live-view implementation. The DNG raw files also integrate much better with iOS thanks to the large preview JPEGs. This makes it possible to use an iPad when travelling - something which was nightmarish with the M262 files due to the low-res preview and Apple Photos refusal to display RAW directly (and shooting RAW+JPEG causes the importer to frequently crash under iOS11).
FWIW, I do not find see any significant difference in image quality, other than improved DR at higher ISOs which makes ISO 3200 and 6400 more usable (but then my 262 never showed any image banding even when pushed heavily, so maybe I was lucky before).
It is a very good camera, but the changes are small and incremental unless haptics are your priority.