This is a pricey lens, but a superb one that delivers the goods and operates utterly slickly in every respect. The range is also really useful, reaching the magic 400mm in a compact optic that offers weather sealing and very close focusing.
Outstanding sharpness, Low flare, Attractive bokeh, Modest distortion, Low CA, Moderate to low vignetting, Fast, accurate and virtually silent AF, Weather sealing, Reasonable weight, Excellent ergonomics