In my experience, the Canon 35mm f/2 is an excellent lens: fast, sharp, contrasty, compact, lightweight, handles well. It's an excellent match for the M2. It's definitely better than the Canon 35mm f/1.8, although the latter is a decent lens. They're both better for everyday shooting than the Canon 35mm f/1.5, a "superspeed" lens whose design sacrifices other image qualities in the interests of maximum speed. The Canon 50mm f/1.4 is also an excellent lens, fast, sharp, contrasty, not too large or heavy. The Canon 85mm f/1.9 is a decent portrait lens, eminently usable, and reputedly better than the older Canon 85mm f/2. The Canon 85mm f/1.8 has a reputation as an excellent lens, but is hard to find and expensive. All of these Canon lenses are characterized by durable brass and glass construction that keeps them usable 50 years after they were built, provided that they have not been severely abused. Brand-new Leica lenses may be better (my Leica 75mm f/2 manages to combine sharpness and high contrast with smoothness, and handles well), but they are a good deal more expensive. Canon lenses are still good enough to take excellent pictures, and when value for money is factored in, they are an appealing choice for photographers more interested in taking pictures than in flaunting status.
