Have used the lens for over 3 years. I think it is fantastic value for money and from 35mm - 130mm, the lens is faultless. Below 35mm some softness creeps in, getting worse the closer to 28mm you get.
Above 130mm camera shake starts to become a factor in handheld shots, if using a tripod then this is not an issue.
There is some image distortion at the extremes of the focal lengths but this is not bad enough to stop me regularly using both 28mm and 200mm.
I still use mine and am overall very pleased with it.