True, it does soften the bottom up a bit and opens it up mid to top.
2013 is more bottom to mid. Most folks around my area are running the 57 to soften the bottom and gain the run time.
That is in buggies. Those that run Trug are running the 13 for the bottom snap. I actually preferred the 13 in my bug, but decided run time was more important so I stuck with the 57.