I have been extremely impressed with Sigma recently.
For example, the latest 35mm f/1.4 lens from them is something that I would want over the other options, and it just happens to be less expensive as well.
If this lens has the same quality to it, I will expect it to do well.
This lens made me think for a bit that staying in APS-C might be more desirable than going full-frame. I am looking forward to the reviews on it.
Canon 5DIII, Rebel XTi/400D
Canon EF 16-35mm f/2.8L II, 24-105mm f/4L, 50mm f/1.4, 70-300mm f/4-5.6 DO, 85mm f/1.8
Sigma 150mm F2.8 EX Macro
Sigma 10-20mm f/4-5.6 EX, Canon EF-S 18-55mm f/3.5-5.6 II
Canon 430EX II
Opteka 13mm, 21mm, and 31mm extension tubes
Vivitar 50mm f/1.8 for OM System