This is the "Nifty Fifty" with a twist.
This is a must have lens to have in your gear bag. It's a great lens to throw on your body (either crop or not) and get right out there and do some incredible portrait and street photography. You will not be disappointed.
Excellent portrait lens for both Full Frame and Crop Sensor bodies; Equates to approx; 85mm focal length on Canon 1.6 crop sensor cameras; New STM (Stepping motor) for silent and fast (although not blazing fast) focusing Very sharp lens; Do not let the price fool you.
Not really a con, but Smaller filter size (smaller than the standard f1.8 50mm Canon without STM; I recommend bying a step up or step down ring for filters anyways to keep your filter arsenal ready for most any lens in your gear bag.