haven't tried any other rom other than Jelly Belly....i am on v3.6 now with frankos 220 kernel.
last night from the time i left work to when i went to bed. left work with roughly 70% battery, had 1% when i put it on the charger at night.
it was 7 hours 20-something minutes, 2 hours 35 minutes screen on time, that is mostly forum browsing, downloaded a few apps from the web, and installed them and rebooted, did about 40 minutes of Gmusic streaming, downloaded a song, took a few pics, did some google plus posting/checking ect. it was probably 50/50 wifi/4g, some texting, lots of forum browsing/posting.
it was a very busy afternoon...and JB got me though more than ICS ever would have.
I'll give it a good go today with a 100% battery and post tonight.