These new water cooled systems are SEALED systems, warrentied for at lease 50,000 hours. Astek originally came out with this system about 4 years ago, and now several other manufactures have jumped in to make them too.
Having owned the older water cooled systems before, this is so much better in that it is a simple "plug and play" without ever having to worry about leaks, liquid evaporation or liquid replacement over time.
The other nice things are that it cools as well as any top end air cooler (and usually better), easy to install (unlike some of the newer large air coolers), and is quiter on the ears.