7 out of 10 points and recommendedAffordable, Solid, Sharp at most apperaturesSlow focus - Especially in low light, very noisy
If you need 2.8 then you probably want a lens that focuses well in low light. On a Pentax K100d, this one does not. In low light it makes a ton of noise racking end to end and often can't lock at all. Even in good light it is noticeably slower and much noisier than the 18-55 Pentax kit lens. I often find myself switching to manual focus out of frustration. It's actually faster even though switching to manual on this lens is a comparatively slow process as well.reviewed August 11th, 2008 (purchased for $199)
I've missed several shots , scared away wildlife subjects and disturbed the low light mood in a quiet church waiting for this lens to finish whirring and clicking its way to a very, very slow and noisy focus lock. Did I mention that this lens is slow and noisy when focusing? It's like reading this overly wordy review kind of gratingly slow and noisy. It's slow and noisy.
That said, the quality of the images eventually produced by this lens are crisp and clean at every F-stop beyond F 2.8, where it is soft but in a nice buttery, glowing sort of way. Basically, if you have time to manually focus your shots this lens is still a good value at the sub $200 price I paid.