Should I Upgrade iOS on iPhone From 5.1.1 to 6.1.2?

I Did Jail-broking my iPhone 1Years Ago. And Kinda I'm feeling like my battery is weaker now somehow.
should i upgrade to 6.1.2(newest version)? Or its still buggy or not recommended?
i don't want to jailbreak my new iPhone system tho, if i decide to upgrade!

Yes, upgrade.

For me upgrade from 5 to 6 made cellphone much faster and battery usage didn't change, Best reasons for upgrade is "don't disturb" so that you set it to sleep without disturbance, If you have really important things the ios6 bug that cause access to some parts still is but I never use passcode lock. I recommend you to upgrade, All little things that are upgraded are nice.