Looks, Height, whatever.....
Dude. With the AMD Sockets.... Installation is a no-hassle, no-brainer cooler. All you do is thread the clamp bracket through the cooler. Just make sure you install the Fans AFTER the actual heatsink is installed.
I mean its about as tell as a noctua. But.... You have a 912.... Plenty of space. there isn't gonna be a mid-high end CPU cooler that isn't gonna be huge in your case. I got a Full tower and the thing still seems a little big but nothing compared to the space i was given. ANd before i had a enforcer.... The CM Storm Cousin to your 912.http://www.newegg.com/Product/Product.aspx?Item=N82E16835181011
And the Cheaper one:http://www.newegg.com/Product/Product.aspx?Item=N82E16835181012&Tpk=A50