I purchased this product in Apr 2017.Quad core processor is good and has good and smooth speed during navigation.
Drawbacks:
Phone heats up more than usual after prolonged(4+ hrs) of internet usage.
No OTG support which is very bad.
No hybrid slim slot.
Small screen.(Larger screen devices available for this cost.)
Comparitivly average loud speaker quality.
Advantages:
Battery lasts for 3+ hours on normal internet usage. Drains very fast on gaming(usual).