xfx 650w core edition,
ocz modxstream 600w pro
Without a doubt the XFX ProSeries 650W Core Edition (P1-650S-NLB9) is best of the three. It's even made by Seasonic and has the longest warranty of those three.
Whether or not it's sufficient to properly power your system is another matter. You need to provide information about your CPU and graphics card(s).