Sigma has been challenging the competition with its Global vision line-up. The combination of “no compromise” image quality and fair price is exhibiting quite a bit of pressure on such brands as Canon and Nikon. And the recent launch of Sony E mount Lenses will surely disturb Sony’s glass business as well (might simultaneously drive Sony’s mirrorless business by providing true 3rd party lens support). In 2013, I bought my first Sigma 35mm f/1.4 Art prime and till this day, it never leaves my camera bag. Since then, I have added Sigma’s 85mm f/1.4 and 135mm f/1.8 Art lenses to my arsenal.