PureOverclock published a review of the ZEROTherm Core i5/i7 Coolers: Nirvana 120 and Core 92 heatsinks. A quote from the article:

ZEROtherm is a company probably best known for creating buzz surrounding their butterfly cooler design not long ago. Capitalizing on that success, they have two CPU coolers for the Intel Core i5/i7 platforms: the Nirvana 120 PWM and the Core 92 heatsinks. The Nirvana certainly looks very unique, and the smaller Core 92 is attractive, but what about performance? Can they keep a couple of Socket 1156 and 1366 chips cool? Can they handle overclocked Core i5 and i7 monster CPUs? Let's find out.

>> ZEROTherm Core i5/i7 Coolers: Nirvana 120 and Core 92 Review