The lens did however have a rocky start, with early models suffering from an internal flare problem , forcing returns and delaying wider distribution. These issues seem to have been solved now though, and certainly the versions we've tested exhibited no problems in this regard.
Useful wide to short telephoto range; Effective anti-shake IS capability; Fast and quiet USM focusing motor; Polariser-friendly internal focusing
Relatively expensive (at list price; Corners slightly soft at telephoto end; 24-70 f/2.8L has better build and focusing; 17-40mm f/4L an affordable alternative