Madstork... as I said my friend tried exactly that, he not only had to buy them regularly they did eventually kill his system. And as far as claiming warranty, I guarantee you will need to pay shipping the dead unit back to the company to do so. You won't see those cheap nonames offering paid for shipping or cross-shipping for their pieces of junk.
Something also not compared is the efficiency of these units... these cheap offbrands are lucky to make 70% as a best case scenario. Any good name PSU will get above 80% now. So 10% of 450W is 45W. Assuming a $0.10 kWh electric rate and 24/7 computer use, that means you spent $3.24 per month extra in wasted electricity. In my view it doesn't matter how you cut it, efficiency savings and not having to pay for RMA shipping, and not having to buy a new unit more than offset the higher initial price.
Core i7 4770k 4.2Ghz
Crucial Ballistix Sport LP 1600MHz 32GB
EVGA GTX 480 HydroCopper FTW
ASUS Xonar DX
Corsair Neutron GTX 240GB | Windows 7 64-bit
Apogee XT + MCP655 & Thermochill Triple 140mm Radiator
Corsair AX1200 PSU | Cooler Master HAF-X