Originally posted by normhead better IQ, compact build
IQ is pretty subjective. The big advantage to me of the 31 is the smooth transitions and out of focus areas. The limited are compact, but look at my 28 -105. By the time you have the 31, 43, 77, 20-40, they are hardly more compact. They are only more compact if you you can shoot with one focal length. And they require lens changes.
In the lens clubs the 21 ltd. (the only ltd. I own) there are almost 100,00 posts and 614 Ikes awarded for 362 posts.
For the FA 31 there are there are 157 posts, and 81,000 views for 208 likes accumulated over what? 15 years?
Meanwhile in a few short years, the DFA 28-105 has 141 likes, 88 posts and 2000 views.
There's no evidence that a DFA 28 ltd. would pay for itself. There's no evidence that the 31 images are preferred to other images from other lenses or even that there's much interest in one. There are a number of 28s that have received very little interest or participation in the threads. It's kind of a pipe dream for a specific number of shooters given the success of the 28-105 at 28mm.
Then you look at the 18-135, 73,000 views, 773 replies ad and 5700 likes in about 10 years
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You really have to stretch to make a case for the even the 31. How popular could a 28 be?