I am a full time pro and have been since I graduated college with a B/A photography in 1986. Worked as a part time pro before that. I was a Canon guy, I still have a couple of my Canon F-1s. A couple of the old F-1s and a new F-1. Also medium format. I had a couple of Hasselblad 500 C/Ms. I have shot both professionally and for my personal work with large format Deardorffs, Horseman, Calumet. 135 format Leica M, Nikon, Canon.Medium format Hasselblad, Bronica, Minolta RBs and RZs When I first went digital in 2005 I bought Canon. Never really bonded with all the automation.
To me Leica is M. The lenses are small and amazing. The M is unassuming. The M 10 mono doesn't even have a logo on it. When I am shooting on the streets I rarely get any attention and then it is usually other photographers that notice. Unlike my Canons which got attention all the time. When the original M9 Mono came out in 2012 I picked one up and fell in love again with the simplicity. I sold all of my Canon gear in 2015 and went all Leica M then. I now have 2 M 10s and an M 10 mono and I have NEVER regretted hat decision. I love how fast working with a rangefinder can be.
But be aware that a rangefinder is not for everyone and it takes time and practice to master. Learning to use the DoF scales on the lens takes time as does getting focus right with the rangefinder. Understand that I have shot all manually for over 40 years and it is truly second nature to me so a tool like Leica M is perfect for the way I see and work. But if you are one that is totally reliant on all the gadgets then understand that with Leica M there will probably be a learning curve.
I would highly recommend before dropping the $$$ to spend some time with one. I mean some real time, not just a day or two.
Heres an interesting piece concerning the look.
I hope this helps and that i answered at least some of you questions.
Allen