I used to use straight of grain cut bindings only. I did a baby quilt with rounded corners so I knew I needed to use binding cut on the bias. I have to tell you, IMHO, that binding cut on the bias is sooo much nicer to work with! I just made a rectangular quilt and I used binding cut on the bias. It has just enough stretch to it and I was able to get it sewed on just like that (hear my fingers snap?). I am a convert now to the bias binding!! I really don't know what I was so scared about?!?!