I hold, in my hands, what I consider to be the best camera in the world: the Sony RX1RM2. It is not cheap, but it's a steal compared to a Leica M10, and it suits my needs better.
The Sony RX1
I've shot with primarily Leica digital cameras, typically sporting a Leica 35mm SUMMICRON lens (f/2.0) for the past 10 years. Leica is an amazingly strong brand, with great heritage, not unlike Louis Vuitton.
However, I have a tendency with my setup to oscillate between using a Leica body and using a Fujifilm X100 body (I get bored, uninspired, and need to switch). Switching to an X100F, while admittedly a perfectly adequate camera, it was a step down, in many ways -- ergonomics, image quality (especially wide open), etc. This Sony camera, however (particularly the RX1RM2), is a step up.
I've always been a fan of fixed 35mm f/2.0 lenses, though (see photo for the big reveal). The lens built into the Sony RX1RM2 (and all Sony RX1Rs) bears the Zeiss name, which is effectively considered the only brand of glass which holds a candle to the legendary-status LEICA glass.
And, I absolutely love the lens. It focuses closer than 1m, which is something I do surprisingly often (most LEICA glass cannot). Autofocus. Video recording (this is a big one). Smaller, lighter. Equally great ergonomics.
Why Sony over Leica?
Sony has won me over, lately. They're my new favorite brand. They made my two favorite devices: my camera, and my Hi-Fi Walkman.
Here are some random images I grabbed, taken with this camera. Nothing impressive, just giving you a feel for what this camera is capable of. Note, each image is uploaded in medium JPEG resolution, because my hosting platform doesn’t allow images over 25MB!
Cameras I’ve Owned
Panasonic LUMUX FZ30
Canon 5D Mark II
Fujifilm X100 (secondary)
Ricoh GR (secondary)
Sony RX100 IV (secondary)