I know with the MYO cards we have the ability to listen to whatever we want, but i really love the simplicity of grabbing a card and listening to a book from a more limited library, forcing me to find new and interesting stories.
Choice can be a bit overwhelming for me, plus the hassle of sourcing the mp3 files for a MYO make it all difficult.
Im totally happy with family friendly stories geared toward older teens or young adults. Fantasy stories like the Eragon series, Warriors series, or for adults stuff like the Wheel of Time ect.
At the moment I use it more than my kids and have really been enjoying listening to the Secret Garden at night (one of my favorite stories and was delighted to find it included in the club!).