Please get the power edition. I have the 7870 hawk with same form of gpu reactor and can say that it does work wonders. You will not be let down by the power edition.
The MSI PE/HAWK cooler works better on Nvidia's card than it does on AMD's for whatever reason. So yeah it's pretty beastly. Not exactly sure how it compares against Gigabyte's Windforce 3X though, which is really good as well.
While not on your list, I would personally go for the Asus GTX 670 DCUII, because it's the most silent high-end graphics card that I've never heard. No pun intended.