In that specific case the VP450 from antec is the better power supply. Seasonic is a really good brand, and any higher end of a PSU then the one you selected would be an excellent choice.
XFX and Superflower PSUs are the same internals as Seasonic so they are also really good.
The EVGA B2, G2, GS power supplies are also very good. The B1, G1, W series are not that good though (w = bad, b1/g1 = not good but not bad).