Six of one, both are decent MOBO's and the failure rates on both are <3%. The ASRock does offer its 'dehumidifier' cycling but the Gigabyte's PCB has been improved to handle high humidity ... repels moisture.
As far as (INR 50$) depends, if both MOBO's have all the features you want and can afford then go with the cheapest. There are better and worst MOBO's.
/Edit - Neither should be run with a PSU without Active Power Factor Correction (PFC) or an Anti-Surge Protector. My preference is a good UPS (Uninterrupted Power Supply).
They are both decent but Extreme4 the only negative I have for this motherboard is that it slips outside of typical ATX specifications. It’s 3cm thinner than a standard ATX motherboard and as a result may lack secure mounting on the far side since this isn’t a common size, which also means you should be very careful when plugging in the 24-pin ATX motherboard power – as the motherboard may flex.Still a decent mobo but i personally wouldn't buy it