Thanks for the reply, seems like 18-135 is mostly recommended here. However photozone's review is not recommending
firstly, the 18-135 is mentioned with a lot of other lenses... hence, i hardly think that its the "most recommended".
secondly, when we look at superzooms like the 18-135, its always a compromise. u will gain versatility, but u may lose on other aspects like max aperture, sharpness (very subjective really), distortion, etc.
thirdly, the reviews from photozone have to be read in the right context: klaus is a measurebator. he shoots charts and draws conclusions from them. charts do not tell the whole story.
in that review, one of his observations was that the 18-135 suffered from distortion at the extreme end... errm... duh??? thats pretty typical of superzoom lenses. he compared it to the tamron which he felt was better but its really apples to oranges - different focal range, different build quality.
not defending the lens or anything - i've never owned it... i don't think it suits me. my "best lens" is based on what i'm shooting. any macro lens works for me when i go shoot bugs, an FA31 or FA50 when i shoot my kid, and i have a DA15 when i shoot landscape. if i'm feeling lazy and i want a lightweight WR zoom, i just grab the 18-55 and go.
so in short, "best lens" depends on intended use.