Just playing around with a Leica 35mm Summicron 2.0 ASPH lens on a Sony NEX 5 camera. I don't have the NEX 5n or the NEX 7, and I wonder if that makes any difference? I use a Rainbow adapter which is cheaper than the nice Novoflex one. I should really get out and shoot some photos on the street, but it's so hot here in Arizona right now.
I converted the shot to B&W and find it pleasing as well. The lens is relatively easy to shoot due to the manual peak focusing on this camera. Once you get used to it, it's pretty quick.