What is your favorite lens? I have the 24-70 which I LOVE but am looking to add a prime lens to my small collection. :)
You can't go wrong with a 50. This is a great all around lens! Although with portraits, I'm seriously in love with the Canon 85L. The only problem with the 85 is that it's really too tight. I have a 5DM2 but for other crop sensors, you'd have to stand back even further.