I've bought the BST-38 Gold Battery, the model with 2500mah.
I'm using MiniCm9 + nAa ICS-02 kernel (also tested on MiniCm7 + nAa 11 kernel, with the same result).
Tested with 3G or Wifi ALWAYS on, automatic brightness, cpu @480-768mhz (ONDEMAND governor) and undervolted, i get 8-10 hrs of battery life
Sony Xperia L 4.2.2 | Root + Unlocked Bootloader
Htc Desire 4.4 Everlov Pre-Alpha
Xperia x10Mini Pro 4.1.2 - DEAD, RIP..best phone by far, from 1.6 to 4.1.2 rockin \m/
Push the THANKS button if i helped you