Quality is the NUMBER 1 thing to look for in a PSU. If a power supply goes too far out of spec under load, it can fail or damage other parts.
Here are the specs from CoolerMaster.
http://www.coolermaster.com/product.php?product_id=6849
As you will see on the chart to 2 rails have a max combined output of 408 watts. So as long as both rails combined never pass (408/12=34) 34 amps and each one stays under its max rating, everything should run fine.
As a user listed above, The card has a TDP of 175 watts and is almost all cases it will stay below that.
I do not recommend getting some massively overclocked version of the card because it will take more power.
The 38 amps that users like to toss around is a recommendation for a FULLY LOADED system not just the card it self. Imagine the heat sink you would need to remove 456 watts of heat.
What else is in your system. The video card is not the only thing taking power.
Just as an example, my media center has a gtx 650 ti card. Nvidia recommends 400 watts and realhardtech recommends 430, but because my system is fairly low powered the thing runs fine with a 300 watt power supply(22 amps combined). I know this power supply can deliver what it is rated for.
Every system will be different.
You do have to be concerned with ONE thing. The CoolerMaster power supply only has ONE 6/8 pin PCI connector.
In it self, that should say they expect you to be able to pull 150 watts from that connector it self(8 pin, the 6 pin is "rated" for 75 watts).
The card has 2 x 6 pin. So you would have to use adapters to go from molex(LP4) -> 6 pin. Most cards come with them.
If you are worried, dropping to a 7850 would drop you to ONE power connector.