A Sigma lens has a reverse engineered EF mount, a long history of AF problems, quality variations pr. copy, numerous examples of poor service etc. etc. To hope for any chunk of the Canon L-lens customer base, they have to be both better and cheaper and they have to be that over time. If they are consistently as good as Canon over time, meaning years, they can move closer to the prices Canon can charge. The only non-Canon brand that can charge as high or even higher prices than Canon is Zeiss. Because they have proved over time that they are consistently delivering absolute top class products in every department. Sigma, Tamron, Tokina and the rest have a loooong way to go before they are in the vicinity of such a position.
I have the Sigma 35/1.4. I am very happy with it, but I am a long way from joining the Sigma fan club
Do you have the USB dock that allows you to fine tune the focusing of the lens and upgrade the lens's firmware?
Do any Canon lenses have such a capability?
1. Have you ever needed such a capability?
2. The latest Canon lenses DO have this capability but they do it through the camera body, so you don't need to buy a separate USB gizmo to do it -- Just an expensive Camera body. The last time I updated my 5DIII there was a lens FW update option in the menu.