Looks pretty good for the parts you selected, except the HEC PSU. I prefer: Corsair/Antec/PCP&C/Seasonic PSU's, because of quality and warranties. Could you send me a link to that PSU??
I'd also consider AMD 4890/5770 over the nVidia gtx260 216 core GPU, but that is just me. I don't know if they are the same price or better.
I probably wouldn't OC that system on that PSU. It's only rated at about 76% efficient (at best), and has 32A on the combined 12v rails. It might be fine, but I wouldn't use it. Like I said before, I'd rather use a quality PSU over one that might be marginal.