I go out all the time with the DA 18-135 and DA*60-250. I have no issues with the 18-135. The 16-85 gives you more range at the wide end and more lens changes at the long end. The area where the 18-135 is edge soft is covered by the 60-250 so it's not really a problem.
The issue here is WR. You've eliminated most of the decent lenses.
Your choice is 16-85, 20-40 ltd., 16-50, 18-135, 18-55WR, Did I miss something?
MY standard set of lenses is Sigma 8-16, DA 18-135, DA* 60-250, Sigma 70 macro. HD DA 1.4 TC, and 21 ltd and 40XS. I bring along the FA 50 ƒ1.7 if theres a chance its going to get dark. I'd like something WR in the wide end, but alas, there's nothing in that category. While I appreciate the 16mm of the 16-85, it''s a lot more money than a 18-135 and I frequently shoot below 16mm, so it's not an end of the line kind of lens for me. If it's not your end of the line, then it makes more sense buying over the 18-135 just for the extra 2mm, given that it's going to cost you a pile of lens changes from 85-135mm.
The largest single number of images taken with my 18-135, are taken at 18mm and 135mm, and many of those are getting close to a lens change. Cutting that back to 85mmm, at least for me is inconceivable, but avoiding a few changes to the Sigma 8-16 would also be nice. It's six of one half dozen of the other.
The DA*16-50 is ƒ2.8. That could also be important.
You're going to have to make a decision based on what's best for you.
Last edited by normhead; 12-10-2015 at 05:04 PM.