Viper Lair posted a review on the Corsair Nautilus500 External Cooling Kit

As you can see above, the Nautilus500 was significantly quicker to install than the other two kits. The reason for this is that the motherboard needs to be removed before installation for both the EXOS and Aquagate, but not for the Nautilus500. Keep in mind that we're very familiar with the Aquagate Mini and Koolance EXOS, so those times are about as low as they get (for us anyway). We think we can maybe shave another minute for the Nautilus, but either way, a liquid system installed under 10 minutes is pretty impressive.

Corsair Nautilus500 External Cooling Kit Review