Rooting (vzw) Nexus S

I got a Nexus S a few months ago, and it's battery life and signal indoors is/was terrible. Vzw swapped it for two more of the same, and I had the same problems. I currently have a Moto Razr with great signal and battery life, but lousy headset connections and only ICS. My second replacement unit came today, yup, the origional Nexus back. Long story short, do I stick with the Nexus, root it and hope for Jelly Bean 4.2, or do I stick with the Razr?

I've never rooted a phone before, love JB and would really like the new Nexus, but am still under contract with (ugh) big red.

Any and all suggestions greatfully accepted please....