Jono, Yes...this is how I feel. I don't want to waste time figuring our this problem. I'm just wary since QC issues seem so common with Pentax. I just returned the sigma 17-50 for back focus issues. Now I'm taking a jab at the DA*16-50 which you have. Hopefully, I won't need to go through 4 copies before I find one usable. Perhaps my used copy from a guy who has done the sifting for me would turn out to be the wise choice. We'll see.
Thanks for the input!
Good luck with the 16-50, I'm rather pleased with my current one, the others were all bad around 35mm (not at the ends as you'd expect). I don't think you can ever expect this kind of lens to be perfect right to the corners wide open.
I've had problems with Nikon, Leica, Tamron lenses in the past too, in fact, the only manufacturers I think I've had 100% in the past are Olympus and Sigma
Anyway, the 16-50 is a nice lens, small for it's range, nicely made, weathersealed of course, quiet focusing - I hope you enjoy.
Incidentally I really enjoyed your post about rangefinders on that other thread; you summed up why my M9 is most important to me much better than I ever could have done.
all the best