Looks like the ultimate travel lens! At 35mm it will also do for a decent portrait lens on APS-C!
I'm becoming more and more a Sigma fanboy
+1 if: the IQ is ok & the price not on Canons pricing orientated
Don't expect it to be cheap. It's a unique lens, and Sigma will take its toll for it. Also, it seems that they didn't spare on special glass and on glass in general (810g!).