I haven't had any troubles with any part of the lens range. All the zoom measurements on these lenses is x1.6, so the 200 is actually 320mm which is really plenty far enough. The image stabilisation must do a pretty good job, as I can easily hand hold a 200mm zoom photo at 1/30 sec.
I have shot in full daylight down to night, and mainly of people, and I find the lens fantastic. Pictures are always sharp, but I am comparing to point and shoot cameras in general. We have an Olympus 7MP 18x optical zoom that was our 'big' camera before the SLR, and I liked the photo quality of that, but the SLR is awesome! We also have a Canon A2000 10MP, 6x optical that my wife keeps in her handbag, but it is ridiculously slow when a flash photo is taken before it is ready to take another. The SLR is quick at focussing and being able to take multiple images, which I do have the camera always set on.
The lens takes fantastic macro shots, set the camera on AV, set the aperture to 5.6, and full zoom, and it will give a really shallow depth of field for photos of flowers etc. If I had some photos uploaded, I'd link them for you but I don't.