Think you made a great choice in cameras. Love my K20D. Not sure what glass you are looking for used. Its out there - some are expensive (85 1.4, 200 macro. 300 4.5). Some are very reasonable ( screw thread, K mounts - 50, 135, 200.
Why worry? Canikon doesn't have lots of bargains on great lenses. Geez, how many image stabilized lenses do they have? Talk about trying to hit the lottery.
Also, remember that with the right adapter you can use Pentax 645 or 6x7 lenses (still with image stabilization). Have a 6x7 165 2.8 thats great to use. Pentax hates obsolesence!
Will Pentax be around forever? Who knows. Don't know that about Canikon either. Who who have thought GM & Chrysler may have to merge to stay afloat and prosper? My guess is Pentax will be around even if they have a new owner.
Will Pentax go FF? Possible. Will your DA lenses work on that body. My guess is yes. Its easy to crop a FF to apsC or apsH. Then your lenses would work. Nikon has already proven it works on their FF bodies. Will you lose some megapixels? Sure, but in a few years time we will have so many it won't make a big difference!
Enjoy your K20D its a fine camera. My favorite of over 40 owned. No matter what comes out in the future it still takes great images.
Thanks
barondla
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