Originally posted by AndrewG NY I had always heard that the FA 28-105 f/3.2-4.5 was pretty good, one of the best standard zooms that Pentax had released for film. I don't know whether or not Jonas B. has better information. The focal length range is rather unattractive for digital bodies however, so I doubt we'll be seeing it (or the also nice and somewhat more useful for D-SLR FA24-90 f/3.5-4.5) again.
The DA50-200 f/4-5.6 is a current lens and is the only telephoto zoom offered by Pentax right now. I'd say the likelihood of it being retired soon is just about zero.
I don't know if I have "better" information. What I have is first hand experience from the FA28-105. It is not the best lens for anything in my experience; it is not very sharp (but quite alright, don't get me wrong), not very fast (but decent), not very good build (but ok). It does lack from Quickshift as allready pointed out and there are several reports about focusing problems with the DS. I also had thse focusing problems which showed up as "don't lock focus". This was puzzling a couple years ago as many had good experience from the lens in the film days. Now it is a bit long at the short end and not a very good performer at the long end.
For bokeh - the DA50-200 has relatively good bokeh as we have seen in many pictures here. I guess it isn't stellar at the end long but that is a problem it shares with most zooms. The important thing is that it is good, functions flawlessly and is a lot more conveniant as it has QS.
For me it would be a no-brainer to choose the DA50-200.
Overlap - yes, many likes this. I guess I would do tha to provided that I used any zooms at all. Now that I use primes only I'm used to switch lens so I'm not the right person to say anything about this.
my 2 cents,