Intel at the current time is only limited purely by voltage with high end coolers, even AIR coolers won't usually hit the actual thermal limit. The Dark Rock 3, that's BeQuiet if I'm not mistaken, and is comparable to any basic tower cooler. However it is quite a bit quieter, and better looking. The Noctua NH-D14 is likely going to be optimal air cooler, where as an H110 or similar will probably net better overall cooling, and sound to cooling ratio. However like I said, you'll hit voltage cap before you'd ever get near thermal capacity. It's like 1.3vcore max safe for Haswell E so maybe 1.35 if you're ballsy.
