Considering A77: advice appreciated
Don't worry, your Sigma is a overall better lens than the Tamron. HSM and sharper at 200mm. The Sigma HSM II looks the best IMO in this comparison.
Phil Reese wrote:
I have heard that the Tamron is slightly sharper, however I love my Sigma 70-200 EX f/2.8 HSM II. It is very close in sharpness, but the focusing drive system is much better. It's fast, and silent (great for video use too). I don't mind the size, but that's just me.