Both are your standard all-in-one liquid CPU cooling solutions. Both support current Intel and AMD processors, come with NZXT FX-140 PWM fans, and NZXT promises 36% more cooling surface area for the radiator. The X40 comes with a 120 mm radiator and the X60 comes with a 240 mm radiator for those with the room for it. Both only come with push fans, but do support additional pull fans for improved cooling.
The NZXT Kraken series features HUE which allows you to change the colors. There is also a dashboard control system for Windows to give you on-the-fly performance figures and control. These are not new to these kinds of coolers, but definitely welcome additions that all value to the Kraken.
We are left like the release of the NZXT Havok 140, their first CPU air cooler, since we have wait and see what kind of performance we get from the Kraken. Priced at MSRP of $99 for the Kraken X4 and $139 for the Kraken X60 as well as a 2 year warranty for both, it is clear the company believes in their potential. If the Kraken series is anything like the Havok 140, then we all maybe in for a pleasant surprise.