if you wanted a pro DSLR the choice is N or C...
if you need a pro rfdr there is also Leica.
The pick of the Canon rfdr is the Canon P the Nikon the S3 the Leica the M2 (or M4-2 if you can tolerate ugly) .
They all have the same shutter the Canon is stainless steel and noisier.
The Canon is cheaper and you have the option of the 60s lenses in single coating or the Cosina in multi.
In UK good P and slow 35mm SC or MC less than 500 GBP from dealer.
You load 400 ISO use ID68 for 650 prefocus at 7 foot /125 and 5.6 fast draw and fire like Gary Winogrand in their face.
Though Gary used a 28mm Canon on his M4 mostly.