Thus, it comes down to song selection and how customized the custom radio features get. And perhaps, it's because Pandora and I have been together for years while I'm still on my first date with iHeartRadio, but I just get the feeling that Pandora knows me better. There may be something to the fine tuned algorithms featured on Pandora, as I found a better selection of music that I wanted to hear when listening to similarly programmed stations on both services. For example, when listening to my Mumford and Sons station, I heard multiple tunes from the band on Pandora while only hearing one song through iHeartRadio.
In addition, Pandora played songs that appealed to me from both known and unknown artists. iHeartRadio may boast the larger music collection, and I appreciated the option to selectively discover new artists or listen to familiar ones. However, it was on their site that I seemed to experience duplicates a bit more frequently. Again, it is likely that a lack of knowledge of my tastes that Pandora has had years of experience suffering through was largely responsible for the lack of familiarity. In the end, is it worth breaking up with Pandora just because there's a younger, flashier and potentially cooler alternative? This listener will remain faithful, and it will be interesting to see if others will do the same.