Best Music Streaming App

Here I am at the holidays, and as a gift for myself (and my family?) I decided I wanted to finally buy into a music streaming service. But I don't know where to go, Rdio or Spotify? Any suggestions? I've used both on trials/ad-supported, but I just wonder what the real differences in their services are, especially with Rdio's new app update. One important point for me is offline. I go offline a lot, both with mobile and laptop.