Yes, at 1.8 it does not produce the same quality as canon 50 / 1.4 or any sigma. Because the lenses are of different price ranges, but in its class, for its price, it is really handsome and deserves to be in the bags of all canon owners Examples:
Canon EF 50mm f/1.8 II Fixed Lens - Discontinued by Manufacturer
93 Review
Nikon 50mm f/1.8D Lens: Perfect for Nikon DSLR Cameras!
97 Review
π· Nikon AF-S NIKKOR 50mm f/1.4G Lens with Auto Focus: Perfect for Nikon DSLR Cameras
76 Review
New Nikon 18-105mm Vibration Reduction π· Zoom Lens with Auto Focus for Nikon DSLRs
104 Review