This is a great 400w PSU for the price:
http://www.ncix.com/products/index.p...c&promoid=1338
I know some of the Corsair PSU's are re-branded Seasonics. From every review I've read people have chose the Corsair PSU's over the OCZ's. The Corsairs power delivery is constant and consistent.
As for Corsair series; The AX is the most efficient (Gold standard) and it's fully modular. The HX is modular except for the 24pin and CPU power. The TX is the non modular version.