Links fixed now.
There is only one version of the 150-500mm lens. They have HSM and OS, except Pentax doesn't have OS due to built in IS in body. Definitely leaps and bounds above the older 170-500mm as I have it as, well, and it's a great lens, but not in comparison to the 150-500mm, like comparing a non-EX to an EX lens.
I will dig up some samples from it. If not, I will take a few with it.
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