Power supply, like other hardware also comes with various prices and quality. Don't spend your money on cheap power supply that will make you regret after buying. When I was buying a new computer a few months ago, I was recommended the Simbadda Power Supply. It cost me about US $45. They also offered me a cheap power supply that cost only $10. I bought the $45 one. It seemed to be quite expensive for me, though as I had spent quite a lot of money on other hardware.
I don't know how good it is until a few days ago, a short power failure at my home. The lamps and fans were suddenly off for about 5 seconds, just a while. But what amazed me was that my computer was still running in that 5 seconds. I thought this could be advantage gaining from the better power supply I had bought that saved my computer from being off for about 5 seconds. Almost forget to tell you. Until now, I'm still not using a UPS.