I had a chance to shoot with the little Pancake Color Skopar 35mm f/2.5 PII this weekend. I purchased this lens for only $350 in new condition with hood and filter. Still under warranty. Great value. I prefer the focus knob over the Leica ones, it does not have hard edges and the focus is fast and precise for my taste. It is a very tiny lens too, of course they call this a pancake for its size and shape. Now on my 3 and 4 day of shooting with the Leica M. I am still deciding on whether I like the rangefinder over a pentaprism viewfinder. I still find the Olympus E-P5 to be my favorite camera vs Leica rangefinders and Nikon DSLRs when it comes to handling but image quality right now goes to the Leica M and Lux-M combo. I see now that shooting with a 35mm the focusing is more forgiving, specially at f/2.5 but I still can’t find my touch on a 35mm view. I always prefer 50 or 85mm it seems that my eye finds close ups more interesting. I focus on single objects vs a wider view. 
ErickPHOTO 