If you keep it on 4.1.
I heard that in the future you may have a software exploited that you don’t need to go into rcm with required hardwar eg. rcm jig.
But for me, I dont mind put in the rcm jig to boot up to rcm mode and launch SX OS or Atmosphere from there.
So I updated my console to 5.1.0
Your choice
Keeping the system at 4.1, wouldn't that cause certain games not to launch because it's looking for an update? I've seen some that don't give you a choice to launch the game, just update.