I will try to keep this review fairly brief as there are several more reviews and much discussion about this lens elsewhere (see this discussion: http://photography-on-the.net/forum/showthread.php?t=934592). I have put the good/bad points and a conclusion at the top for easy access.
Some pictures of the lens with my 7d attached (yes it was raining!):
- Good image quality wide open, amazing when stopped down even just 1-2 3rds of a stop.
- Takes 1x and 2x teleconverters (great IQ with 1.4x)
- Good price
- Build Quality is good (apart from lens hood)
- Very good image stabilisation
- Reliability (a massive negative for some users, not so much for others)
- AF maybe not as great as it could be (although it’s still good)