With the latest two 50mm announcement we now have 58(!) 50mm E-mount lenses according to this BHphoto database . Still, the new Sony and Sigma additions are welcome as both have very high quality and offer a tiny bit of differentiations: The Sony is super compact while the Sigma is a top choice when it comes to balance performance with price. Check out Chris take on both new lenses!

Sony 50mm F/1.4 GM at BHphoto . Amazon . Adorama . FotoKoch . FotoErhardt . Calumet DE . WexUK .
Sigma 50mm lens at BHphoto , Amazon , Adorama , FotoErhardt , Fotokoch , WexUK .