Asus Zenphone 5 is really good. If you plan to buy a phone with budget less than 10K. I have been using this phone for last 1 week observations found,
Very fast processing
Multitasking
Charges little slow
Many people reported battery problem. All you have to do is need to charge the phone till 100% ( led light changes from red/orance to Green) .
Use the phone till the battery reaches 1% then again charge it to 100% . You have to repeat this at least 3 times. Then switch off the auto-brightness option. I have experienced 18-20 hrs of back up if I played games and used internet. Battery will drain faster if you use online games. The battery life max stands for 23 hrs ( usage is only attending calls and sending msgs) .
Design and built quality are really good. Phone started heating at the back if you play games continuously for 30 mins or more.