This isn't to be considered a full review of this lens but there seems to be little info on what it can produce when pushed a little.
I've had this lens on my Super Program since about '84 / '85 & it's done a fine job with film over the years from Hawaii to D.C. with a lot of Naional Parks in between...but I can't wait to do a test on the K10D rather than scanning film images (financier syndrome causing a slight delay). The zoom & focus ring are as silky smooth as when new.
I have the following scanned 100 ASA film print handy from my trip to Alaska last summer at the Totem Pole Museum in Ketchikan. This pic is shot wide open F4 at 24mm, offhand / unsupported, at over 1/2 sec, slightly up-angle for coverage & effect. I was pretty steady that day w/ little shake & was pushed for the shot with tourists walking in...take the shot!