Sapphire is comparable to Asus TOP GPUs, they have excellent PCB construction and components and because they are AMD's biggest manufacturing partner they tend to get the best binned chips at the best price(thats why Sappire is cheaper than Asus but of similar quality).
So definitely Sapphire, try getting a Dual-X or even a Vapor-X version from sapphire. Best cooling EVER!
Now for the rest of your build I really suggest you post links or exact model number for the parts listed.
A few important things to consider.
1. A reliable adn stable power supply is VERY important, DO NOT GO CHEAP! Rather spend more and save your system form damage. Also 750W is overkill. A 600W already is sufficient. Post the EXACT PSU you have chosen so we can advise whether it is decent or not. Chances are the one yopu have is really bad.
2.Great choice is SSD!
3. The motherboard as DarkSable said is not great, there are easier and cheaper boards with more features, the ASRock Extreme4 being one of them. I own it, and love it.
4. 16GB of is overkill but since RAM is so cheap, its worth it.
5. DarkSable has a point AGAIN. The H100 really is not worth the cash, a noctua D14 performs similarly but does not cost an arm and a leg.
The best air cooler in my opinion is the Thermalright Silver Arrow SB-E Extreme.
Here is a comparison between the Noctua and some Closed loop water coolers.
http://www.tomshardware.com/reviews/h100i-elc240-seidon-240m-lq320,3380.html
6. Lastly, the RAM you have chosen. I would suggest making sure they are the low profile version, this will allow you a lot more flexibility for different coolers. Those fins are just for looks, they have zero functionality.