Not sure if you'll be able to reach 5Ghz, depending on your choice of cpu. But if its a choice between the two, get the d-15. Is it worth the money? That's subjective and relative to you really. If it must be an air cooler, the d-15 has proven itself one of the best on the market. However, there are others that rival it in quality and performance. Cryorig R1 Ultimate, Phanteks PH-TC14PE, Thermalright's Silver Arrow and Macho lines, so on and so forth. All listed above, and others I've neglected to name, are flagship air coolers, though the D-15 tops them last I knew, with the possible exception of the R1 Ultimate? Anyhow, yes, the d-15 is an excellent, well built cooler. The 212 evo shouldn't even be mentioned in the same sentence with it imho.
Note: Assuming your case is big enough for whatever choice you go with, remember not to overdo it when you install. Screwing it on too tightly (absolutely no reason to ever do that, but just saying) may end up bending the newer intel chips in time.