Some sample photos of this lens in a "contemporary" setting: a concert stage.
1. 600mm
IMG_1247 by
FreyaEvo, on Flickr
2. 500mm
IMG_1248 by
FreyaEvo, on Flickr
3. 388mm (I thought I set it to 400mm)
IMG_1249 by
FreyaEvo, on Flickr
4. 302mm
IMG_1250 by
FreyaEvo, on Flickr
5. 200mm
IMG_1251 by
FreyaEvo, on Flickr
6. 150mm
IMG_1252 by
FreyaEvo, on Flickr
I have owned the Canon 100-400mm Mark 1 and the Canon 500mm F4 Mark 1. With the naked eye, I feel that this lens is as good as the Canon 100-400mm Mark 1 up to to 400mm. At 600mm, it can't beat the Canon 500mm F4 but the image quality is not too far off.
The main "limitation" for this lens is the aperture. If you get good lighting, the image quality will be good. However, it can be carried around easily and that gives you a lot more opportunities to take photos. The construction is good and I have used it in sub-zero temperatures with no problem. The OS works well and I have no complains about it.
The best way to hold a camera with this lens is using the left hand to support the lens at the front and the right hand at the camera grip (I am a right hander). You can control the zoom by pulling or pushing the front part of the lens. In my opinion, it is the best value telephoto zoom lens considering it's price and capabilities.