One more thing. With Trinity Kernel, I was able to squeeze 2 full days of moderate phone usage on top of rock-solid stability and BLN.
Here is a link for the old derkernel site: http://www.derkernel.com/odk/index.html
Just make sure you choose one of the the "Pre Deep Idle Nexus S Kernels:"
My claim was possible due to me using TEUV-NS-05102011 (0.88GHz with 220MHz bus/gpu,ExtraUnderVolted) kernel. It could lag with some games, though.
A note, deep idle ruined the kernel for me. So the 0510211 versions of the kernel are the best imo.
I'm going back to GB, because I am sick of the unresolved issues around Exchange services on JB.
Best of luck,