I'd go for a Silver Arrow over the NH-D14. It is less expensive than the NH-D14, has 2*140mm instead of 1*140mm+1*120mm fans which are imho quiter (at least compared to the NF-P14). Also it performed on par (even slightly better) at less extreme overclocks on a chip that one will propably not come even close to with a 2500k thermal wise, even with extreme oc.
Also true. But then again i'd rather question large RAM heatsinks tbh. Large RAM heatsinks cause clearance issues with a lot of coolers. Not sure if the NH-D14 is that much better there (not checked).