I've already made up two playlists, one each for a 45 and 60 minute class. The school rec center has both lengths of classes. I'm more partial to the 60 minute classes, that's what I was used to before moving, but sometimes it's nice to be in-and-out in 45 minutes. Plus it gives me a chance to really push myself a little more, since it'll be over more quickly.
Maybe I'll post a few playlists as time goes on! Wish me luck!