Matt White , Feb 04, 2011; 01:47 p.m.
I have and love the 135/2.8, but I bought it because I wanted a fast medium-telephoto prime and couldn't afford the 135/2. If the SF is set to 0, it's extremely sharp, even wide-open. It's also very well-built for a non-L.
I've played with the softfocus on occasion, but it's easy to overdo it. I don't use it all that often. One neat thing about the SF ring is that it doesn't have to be set to the 0, 1 or 2 clickstops. It can be set to anything in between to finetune the effect.