The XFX XXX 650W PSU has 52amps +12v power. The TRX750M has 56amps +12v power.
I think the XFX 650W is the better option. I haven't yet seen any reviews of the TRX750M that have tested it at full power.XFX 650 W XXX Edition Power Supply Review
@ Hardware Secrets. Tested in the hotbox to 100% of its rating.