I love this lens. It is relatively small and light for a f/2.8 zoom, and optically great. My copy is very sharp wide open across the whole zoom range. The optical stabilization works very nicely, and lets me handhold way beyond the conventional 1/shutter speed rule. In terms of the price it is noticeably cheaper than the Canon counterpart with a similar performance.
I am a big fan of FTMF, and unfortunately this one lacks it. However, the focus has been very accurate on my 60D and I have not needed FTMF so far.
I can wholeheartedly recommend this lens.