<p>Hi Hin! I got a 16-60 with "dodgy" SDM, but when it arrived to me it was totally dead. I'm debating having the SDM repaired vs. getting it converted. I have used it on my *ist, and the AF is pretty noisy with screw drive. Also it fails to lock more than my other lenses, hoping this will be better on the K3. Anyway, I think the lens with SDM is preferable for the price difference you quoted (and that's what you are getting, anyway!) Enjoy!</p>