I once bought a PC kit from Fry's Computers, a CA superstore.
First, I couldn't get it to work. I finally had to bring the motherboard back to the store. The returns guy plugged it in to test it, and it worked. I noticed he plugged in a 4 prong connector I''d never noticed, so I asked him what it was. Video power supply, he said. My old power supply was from an older generation, and didn't have such a plug. No wonder I never saw anything on the monitor. That's when I learned Thermaltake's sterling reputation among power supplies. Here's a Corsair v. Thermaltake discussion.
It looks like you can't go wrong with either.
Despite my new Thermaltake PS, my completed computer kept dying. I contacted the motherboard company's tech support, and after a long string of emails with an engineer, and lots of diagnostic testing on my part, the engineer declared the moherboard couldn't handle the power demands of the CPU that Frys had bundled in the package. I got Fry's to swap for a compatible motherboard. Caveat emptor.