The most efficient one.
At the exact same power draw, a Coolermaster Extreme 400 is 75% efficient (approx), based on the behardware review, and the Gigabyte around 82%.
The CM will thus draw around 133 watts from the socket, and the Gigabyte 121 watts.
The difference between the worst and best supplies is only 16 watts, and between first and second place just about 5 watts. Over a 24-hour, one month run that is 11.5 (3.6) units, or about 17 (5) rupees/mo.
However note that the decreased efficiency also results in higher heat output from the PSU, and low quality PSUs have other issues which are well covered in past threads. Ultimately the differences in efficiency come from conscience, not from the wallet. That little bit you save helps overall conservation, so you should get the most efficient supply your pocket permits.