here is the current setup of the six-20. i converted it to 120mm film and got tired of screwing around with those kodak lenses so put a good rodenstock f 3.8 lens on it. i found a chess series v push-on filter adapter for it and now it takes great pictures, huge 6x9 cm  negatives, right out of my pocket. the rodenstock handles color quite well also.

Six-20 / Rodenstock   f 3.8

Above is the comparison of the Kodak f4.5 to the Rodenstock f3.8. A world of difference! The picture quality? Also a world of difference!