As much as I wanted to stick to primes, and as scared as I was about SDM issues, I finally gave into temptation and got a DA* 50-135. And to make the dent in my pocket worse, I snatched up a DA* 55 as well. I've seen too many outstanding images and read too many reviews of professed love for the DA*s that I have to try them. Also, when I shoot portraits, there's too many times that lens changes have disrupted my groove.
I tried to talk myself into buying a Sigma 50-150 instead to feel more confident with AF issues, but I can't loose with the DA* 50-135:
1. I want that Pentax quality I've been seeing in so many images.
2. I like working fast and consistent. (less lens changes)
3. IMO, It covers the premium portrait focal lengths perfectly.
4. I could always get the SDM disabled with no worries in the worst case scenario, because I don't mind noisy screw drives.
With all that said, I couldn't find anything negative enough to stop me from buying it. I was considering getting a DA* 16-50 or DA 15Ltd, but I still can't bring myself to pull that trigger, so I just bought a DA* 55 instead.
"So Your Honor, ....I'm a changed man!!!" I will soon have a zoom again. I couldn't wait to add them to my signature, but sadly I have to wait to start shooting with them.