Last year I was shopping for a super zoom, and ended up with the Tamron 18-270 (the old version). There was a rebate, and I could not find any independent reviews concluding that the Canon (or any other make) was superior, while several gave a slight nod to the Tamron. I have used it a lot in the subsequent months, and have no complaints. The extra length can come in handy, and it gives sharp results when stopped down a bit. For what it is (a walk-around vacation lens) it does the job. In this class, where IQ expectations should be modest, price may be the most important criterion for many people.
