One of the appealing aspects of Intel chips is their lower power dissipation. Unless he's going to be into heavy overclocking, water cooling probably isn't needed. Liquids like to find ways to get out of even sealed systems... But that's just my gut feeling - no personal experience.
The i5 2500K is a nice chip. Note that it doesn't do "hyperthreading" which has its good and bad points. i7 chips do hyperthreading. Just be aware.
There are i7 LGA1155 chips so one could potentially do an upgrade, but check the details if you think an upgrade might be in the future. The i7 2700K is about $125 more on Intel's page - http://ark.intel.com...-Cache-3_5-GHz%29 Beware of churn in Intel's parts list. 2 years from now they might not be available.
Try to find out more about the power supply. You'd like one that is efficient and has high-quality components. Crappy power supplies are very common, unfortunately, and can cause lots of gremlins.
With all that said, it sounds like a nice box. I would think you wouldn't need to do anything to it for a couple of years.
Good luck.
Cheers,
Scott.