I've seen the above lens second hand for £200 and I'm wondering if it would be a nice addition to my lens collection for the times I want to go a little wider than the beast. I've read a couple of threads on here where it gets mixed reactions but I'm wondering if its a bargain at the price I've seen it for. Lack of wide open sharpness isn't the end of the world as it would be used more for landscapes etc anyway where more DOF is required - so whats the quality like once you start getting around over the f4 mark? I've seen the Sigma 20 f1.8 for the same price second hand, how does that compare? Although like the appeal of the more compact Nikkor. So, what we saying...yay or nay?