My advice regarding photozone's reviews is to take as reference, but no more than that.
Reason is that all these reviews focus on the measurables (ie. sharpness, distortion, etc)
What these fail to evaluate are the important for real world usage stuff like size/weight; close focus; rendering/contrast; weather sealing; etc
I did a review of this lens some time back.
To me its a good lens and ideal all rounder. Basically, the 18-55+50-200 combo and then some on just one lens.
Real world use, a lot of the measurables as described on photozone are not that discernible (nor matter for most photos).
The practical implications of this lens not measured nor even mentioned in such reviews, matter in real world use though.
http://www.clubsnap.com/forums/pent...ax-da-18-135mm-f3-5-5-6-ed-al-[if]-dc-wr.html
of course, its only for reference only too...