Upgrade to 5.1.1 from rooted version 5.0.2 - Galaxy S6 Edge G925F

Hello All,
I'm using rooted version 5.0.2 rooted with pingpong. My question is, shell i upgrade 5.0.2 to 5.1.1 or not?
If Yes, what method i shell use to root? Is there any advantage of having 5.1.1?

Thanks in advance...