Selina, the thing to remember about the z is the height of the seat, I know you can cut them down, but it is a big ol' bird. I'd go on what sort of riding you are going to and want to do... to decide. Test rides are a must (although that's hypocritical as I have never test ridden a bike before I bought it) but in choosing between these two I think you probably already know in your head what you should go for..... So ignore that and go with your heart!!!!