I used to be obsessed with iTunes Radio, but now I am in favor of Spotify. iTunes radios having better music standards and more recent, popular music. Although, Spotify is less costly for me, and I am not just talking about the monthly memberships costs. After listening to one song on iTunes radios I have used up to 100 to 150 MB of data, which may not seem like a lot at first, but it most definitely adds up. After listening to one song on Spotify my data has gone up .5 to 2 MB. Not only that, Spotify allows you make playlists and more that simply gives you a better music experience overall.
Don't get me wrong, I will always be an Apple fan in my heart but right now Spotify trumps iTunes.