Nobody can answer this for you. Too many variables come into play in terms of battery life. Everyone gets different battery life. Nobody has your specific device, lives in the same house as you (location), has the same exact apps as you, or uses their device exactly like you. You will need to flash, root, mod your device yourself to figure out if it lives up to your expectations.
Is it faster? Also not something anyone can answer as the results will differ from device to device.