My new Tamron SP arrived today and seems a good one. It was a toss up between getting one of these and the Sigma 24-70mm EX. I took a load of shots indoors and seems to be able to produce about the same number of keepers as the Canon 50mm II, which is my benchmark inside lens. I've attached a shot taken of my pen-knife, a standard lens test item for me; I just applied my default USM, as I do with all images straight out the camera. This is at 75mm. At the wider end it is not so sharp, but doesn't matter to me as I have my Tokina for 20-35. It's nice and lightweight and all seems to work well. Hood fits easily and the front pinch lens cap is SUCH a design improvement over the standard types. Certainly an improvement on my ex Canon 28-135 IS and at least as good as my 50mm II, which is very sharp and reliable (I feel another sale coming on!) Recommended as a very decent indoor and outdoor carry around.