I Shot the 50-140 for 8 Years. Can This Tiny Sigma Replace It?

After eight years on the Fujifilm 50-140mm, can Sigma's tiny 50-120mm F2.8 replace it? Portraits in Philly, a nor'easter, stabilization, the stadium lens rule, and how Sigma's compact F2.8 trinity stacks up against Fuji and Canon.