As for the APO vs. non-APO matter, I once looked up and compared their respective performance data (MTF, distortion, fall-off, chromatic aberration). If one thing I learned it would be that stopped down (f/5.6) and at moderate enlargement (10x) there is no discernible difference between the regular Rodagon 50mm f/2.8 and the Apo-N version. The non-APO is a superb lens.

Have a look at the graphs yourself in this post.