After long time I am starting a thread on TE 
I am using Redmi Note 3 since a year now. Initially battery life was excellent with SoT easily touching 8 hours over 1.5 days with stock Android 5 firmware (I think MIUI 7.2.5 or 7.3.x). After MIUI 8 (based on Android 6), this had gone to low of 4-5 hours SoT over a day or less. From here I moved to custom ROMs for better battery life. I have used Lineage and Resurrection Remix for 6 months now, with Resurrection Remix turning out better of two. In between, I had to flash Global Dev/Beta ROM to get some modem firmware updated. In all three ROMs, I manage to get 5 (or 5.5 at the max) hours SoT in just under a day.
On all my custom ROMs, I root them, block ads using AdAway and use Greenify for hibernating apps.
My usage is pretty high but consistent. I mainly use WhatsApp extensively (approx 2-3 hours a day), Firefox browser (shifted from Chrome as it was keeping CPU awake for long time) (approx an hour), default E-Mail app with manual synch, Clash of Clans (approx 30 mins to an hour), Parallel Space (tried with removing this app for a week but results are same) and some other casual apps which I use seldom. All my accounts have synch off. Brightness is controlled manually. I am always on 3G network and use data network for roughly 1 hour each day at max. Rest of time I am on WiFi at work and home. No Bluetooth, GPS or any other sensor.
I do not know why there is this huge (for me it is) difference in battery life in a year. I would like to know from fellow Redmi Note 3 users about which ROMs they are using and what is their experience.

I am using Redmi Note 3 since a year now. Initially battery life was excellent with SoT easily touching 8 hours over 1.5 days with stock Android 5 firmware (I think MIUI 7.2.5 or 7.3.x). After MIUI 8 (based on Android 6), this had gone to low of 4-5 hours SoT over a day or less. From here I moved to custom ROMs for better battery life. I have used Lineage and Resurrection Remix for 6 months now, with Resurrection Remix turning out better of two. In between, I had to flash Global Dev/Beta ROM to get some modem firmware updated. In all three ROMs, I manage to get 5 (or 5.5 at the max) hours SoT in just under a day.
On all my custom ROMs, I root them, block ads using AdAway and use Greenify for hibernating apps.
My usage is pretty high but consistent. I mainly use WhatsApp extensively (approx 2-3 hours a day), Firefox browser (shifted from Chrome as it was keeping CPU awake for long time) (approx an hour), default E-Mail app with manual synch, Clash of Clans (approx 30 mins to an hour), Parallel Space (tried with removing this app for a week but results are same) and some other casual apps which I use seldom. All my accounts have synch off. Brightness is controlled manually. I am always on 3G network and use data network for roughly 1 hour each day at max. Rest of time I am on WiFi at work and home. No Bluetooth, GPS or any other sensor.
I do not know why there is this huge (for me it is) difference in battery life in a year. I would like to know from fellow Redmi Note 3 users about which ROMs they are using and what is their experience.