I have had the 20-40 for a week and am very happy with the quality on my K3. I have had the 17-50 Tamron and it is a good lens and is well priced. I might get a Sigma 18-35 for specific uses but it is way too heavy for a walk about all day lens. The 20-40 Limited is more costly than the others but it's build and quality are immediately evident. It weighs under 300g and carries great all day. It complements my primes and will get a lot of usage.
I find many of the debates interesting. Cost and sharpness are two considerations but are not the only considerations for me, ergonomics and balance on a camera are also important. I don't put a lot of stock in photographing brick walls, I prefer to look at my own photos and I can say that the 20-40 is worthy of its label. I have several Limiteds and it is worth my considerable investment. It is very sharp by the way, great colour and it is weather sealed which is a bonus.
Each person makes there own choices based on what they consider important. If you want a quality zoom that covers a very useful range, feels comfortable being carried around your neck all day, is quiet and weather resistant, and looks great to boot, buy one. The weight saved will likely mean that I take the 60-250 on more hikes, a great tandem for IQ. Add the DA 15 and I cover everything I want.
Last edited by Primes4ever; 12-11-2013 at 05:05 PM.