Limbwalker wrote in post #17465640
We'll see. If it didn't say SIGMA on it, I might agree. For QC, I've had much better luck with Tamron.
The panning OS and software dock will definitely attract folks to it.
I've had such good luck with every Tamron lens I've ever owned (and such bad luck with every Sigma) that it would take a lot to convince me to lay down my Tammy for this one. But I hope those who buy one are happy and they have worked out their QC issues.
I, too, have had great luck with Tamron lenses, and the 6-year (US) warranty provides more peace of mind than other makers offer. Now, while I have unloaded Sigma lenses in the past, I really like the 30mm 1.4 Art, and I expect that the Sigma 150-600 C will be a good lens. I also like the Sigma dock, and think that it will be a feature that will attract buyers to the Sigma 150-600. However, there was no Sigma 150-600 when I bought my Tamron, so I have a year's worth of use that the Sigma could not have offered. Also, since I have had great results with the Tamron, I don't expect that the Sigma, even after adjusted using the dock, would give me better results than I am getting now.
As far as the VC and panning, I don't shoot air shows and keep my shutter speed north of 1/1000 sec for birds, so while this may be an issue in some circumstances, it has not affected me.