With updates often comes bug fixes, and when modems are updated it can often mean better call reception and better data connections. Better data connections can mean improved battery life and an overall better experience. You may not be inclined to update to the latest leak if you are pleased with your current rom setup. Thanks to developer "Invisiblek" you can install the new modem over your current rom. Head to the source link below to grab the new modem and simply flash in custom recovery!