are you going to sli? if so that psu is fine if not you can do with a 650w. if you are going to sli those cards you should add a 200mm fan on the side panel. nzxt cases require nzxt fans. or you can just get a silverstone raven rv03 which has better airflow.
^ The Ripjaws are a few bucks more, no need to nitpick that.
Hardly. The Hyper 212+ can handle pretty solid 4.6ghz OC's with an extra Slipstream on it. For that matter any high RPM/CFM fan.
Also, not worth it. The Seagate offers the same performance with a 500gb platter assuming it is the newer version (7200.12) if you can save save. The F3 will not offer that much more performance if any.
I do agree on the card opinion, I disagree with the card suggestion though. 2 SLI 560 Ti OC's would be similar in price but better performance by a huge margin.
all you will need to power that is 750w. pc power and cooling makes a 750w version of the psu you posted. it is also silver rated and it is 99$ after promo code so it is a very good deal for a silver rated psu.
Ive had SLI/Crossfire before. I would prefer the fastest single gpu card then 2 lesser gpu's in sli/crossfire. While a decent amount of games work with sli/crossfire, there are those that dont at all, and even actually some that take a hit to performance. You get a lot more heat in the system with dual cards too.
btw, a gtx570 would be fine for 1080p gaming