If you're planning on overclocking then the Phanteks CPU cooler or the NH-D14 (I believe Phanteks are the OEM of Noctua?) Both coolers are essentially the same.
If you're on a budget and plan on doing some light/mild overclocking, then my recommendation would be the Coolermaster Hyper 212 EVO for only £22, compared to £80 odd for the NHD14.