I'd really like to recommend this, there's a lot to like, Lenstip's review is right about the sharpness, colour and superb VC. However my experience means I can't - for me you're taking a chance with a Tamron. I've had 3 of these in 1 month, all sent back as defective.
Price if copy is good (especially now it's dropped for earlier unrealistic expectations); Sharp at f2.8, very sharp by f4 (at least where it does focus), build is decent for price; VC is extremely good; 3-position focus limiter useful; Hood (are you listening Canon
Tamron's woeful quality control (hence value for money = 0); Focus not quite as fast as Canon USM