One of the virtues of the 16-50 is the weather sealing, of course. At the time, I only owned that, and the DA*50-135, and it was a great two-lens kit for motorcycle touring. In a case like that, zooms are just a lot easier to deal with and use while on the road exploring unknown locations. I plan on doing a lot more motorcycle touring and camping in the near future, thus my renewed interest in possibly re-acquiring a 16-50.
I was reading a "ride report" on another forum, about a guy's motorcycle trip from Arizona to Alaska, which has really sparked my imagination. He's a fellow Pentaxian, using a K5 and the DA*16-50 (plus a couple others), and came up with some really amazing shots:
WAY UP NORTH - To The Arctic Ocean & Back to Arizona - ADVrider
So it all depends on your needs. Tamron and Sigma equivalents are also good lenses, but, at least for what this gentleman did, it was the perfect choice, and I don't think you can argue the quality of his work. (And I hope those of you that follow the link enjoy the thread!
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