7 out of 10 points and recommended
Just like the other person I also decided to take a chance and buy the lens.reviewed July 4th, 2008 (purchased for $500)
The lens OS system makes a noise for about 1 min, since it been operating even if you don't focus or use the camera, I am not sure about it using battery for it all this time, that has been discussed in details somewhere else on the net.
You can't manual focus while in auto focus mode.
I had a problem with the auto focus becoming very slow once, but it resolved it self after taking the lens off the camera and putting it back on. I hope it was a one off, but please tell me if anyone had the same problem.
As for the better side I find the HSM focus to be normally very fast.
The picture quality is good but not the sharpest, the Sigma 17-70 I had before is sharper.
The range is very good, although at 18mm there is strong barrel.
As for the OS system I managed to get good photo at speed of 30 on 125mm, anything below it came blurry. So really if you don't try extremely to be steady I would say it is 2 stops down.
Beside that the lens is quite small and light for it zoom range, which is very handy.
Make your decision. Unfortunately at this range there is not much competition. Maybe just 18-200.