The Topcor 35mm f2.8 impressed me. I really like the rendering and bokeh. The lens can also be very sharp in good conditions.
Mine has the exakta mount.
Her some samples :
sunset of peace by G. Don, on Flickr
jellyfish spotting by G. Don, on Flickr
Down the dune by G. Don, on Flickr
Anchor Rope by G. Don, on Flickr
in the small streets II by G. Don, on Flickr
sweet dog by G. Don, on Flickr
hey waiter by G. Don, on Flickr
vintage balls by G. Don, on Flickr
Delft by G. Don, on Flickr