Originally posted by Another dyemention That's fine if that will be the case. While I would prefer a 70-200 zoom, with the 50-150, I can always add the da200 or the 60-250. It puts me in a nice spot right in the middle so I can work from what I have. I know the 70-200 is probably better suited to the whole concert thing, but I feel like I'd leave it at home for other occasions due to it's size. I feel like is be wishing I had a smaller zoom like the 50-150. So I think I made the right choice in purchasing the sigma. I actually just sent the payment half an hour ago so I'll be looking forward to using it soon.
To me if you decided for the sigma, it make no sense to buy the tamron, that would be wasted money because they basically do the same thing. We proposed the tamron because it was the best bang for the buck.
Sure the sigma start to be a bit too short for wildlife but for concerts, portraiture and low light in general it would do just fine.
As for the weight, even the sigma is heavy/big. significant less than the tamron, but if you don't like big lenses, and you have both you'll never want to take the tamron anyway and you'll complain about the sigma.
I know that I sold my 50-135 for that reason and gone FA77 + F135. A bit lighter... I can let the F135 at home when I don't want it (so FA77 alone much later) and quite smaller too. I get even more picture quality and outstanding rendering, in particular from the FA77, but loose the comfort of a zoom.