Well I only have the Serenar version of the 1.8, contrast wide open is pretty mellow, little more as you stop down. Bokeh is very nice, smooth, the apature opening is almost perfectly round. The build quality is on the same level as a Leitz lens in my opinion. I had to take mine apart to clean some condensed oil off of one of the inner elements when I got it and it was very easy to take apart from the rear. I did not take the front element out though. I paid only $125 shipping included for mine from evilbay.The 1.4 version usually go for around $200 for a good copy. The only drawback is the 40mm filter size on the 1.8. I purchased a 40-40.5 adapter, uv and vented hood for about $25 and that solved the problem. I will post some photos from it shortly, I have a few frames left on this roll and once developed I will edit this post.