According to me this is still the best budget phone in the market. It provide better spics at low price. Its battary is very good after a havey useage it backup atleast a 1 day.
Hybrid sim slot :
According to me it has major problem of this phone that it have hybrid sim which means you can use 2 sim or 1 sim and 1 SD card at one time.
Body :
Xiaomi provide Metal unibody which is good , which looks very primium, they don’t give just a plastic body.
Sensors :
It is very good that Xiaomi gives almost all sensors in their phones like Accelerometer, Proximity, Ambient, Light sensor, Gyroscope, Fingerprint but they did not give fingerprint in ₹7000 phone which is Redmi 3S, and many more sensore it provide.
Processor & Ram :
Xiaomi Redmi 3S Prime have 1.4GHz octa core 64b-bit processor which is based on Qualcomm Snapdragon 430 chip set and it have 3GB Ram but in Rs. 7000 model it have just 2 GB Ram. But the GPU it have Adreno 505.