8 out of 10 points and recommendedImage sharpness, zoom range, sharp at 600 [stepped down], VCDust under front element, VC useless for airshow display use.
As regards image quality, the results can be stunning but you have to get used to its characteristics to achieve them. VC takes about a second to kick in but when it does it's top notch. Panning shots with VC on presented no problems in the horizontal but any other angle threw it off, such that air display shots were better off without VC. AF is quick and silent and on the whole very accurate.reviewed October 2nd, 2014
Zoom and focus rings turn very smoothly with just about the right amount of damping; pity the sealing is not up to the same standard, seeing that dust soon appeared under the front element. As already stated, image quality can be stunning, with very good contrast, punchy colours and excellent sharpness. It gives best results in the mid aperture range - f8 to f11 and unlike most zooms, stays sharp even at 600 within this aperture range. Very low CA and low vignetting on APS-C size sensor.
All in all, considering what it costs, I'm pretty happy with this lens and would recommend it any time.