From the picture you shown, the sharpness of this lens at f8 is really disappointing, I think 18-70mm is still sharper. Please correct if I'm wrong.
probably becos i din use MUA (not sure it has), and the tripod i was using is the manfrotto 7-series travel tripod. not exactly top-drawer stuff. i'm pretty sure if i use a sturdier tripod, the camera shake will go away.