Train has made some good songs other than just "Hey, Soul Sister." I'm glad you've taken a liking to them, even though I'm not very fond of them myself, nor do I listen to them very much.
I have a burning hatred for 'Hey Soul Sister,' but the album and the singles they released before that are great. Their album 'For Me, It's You' is really good, and so are some of the songs on 'Save me San Francisco,' their latest. Like the title cut on their most recent especially.