for sports... still considered slow... faster a bit is sigma... but i dun like the peeling problem later... tokina is still slower than sigma i heard...
It depends on what you shoot. Tamron is famous for its sharpness, but its focusing speed is quite slow. If you're shooting sports or events, you might have missed a lot of great scenes. Wedding is okay, I suppose. (personally do not use 70-200 for wedding, it's just too long @.@)