If you go with water-cooling, just be sure you know exactly what you're getting into. Remember -- it's water and electronics -- something's just bound to go wrong...
Keep in mind also the modern 'blower' style heatpipe ridden air coolers also do a great job, with no fuss involved.
But if you want to tread down this path, just be sure to be as careful as possible or you're bound to have disaster. Make sure you get only quality components, down to every nipple and tube. Also, make sure you o/c the cpu enough to at least get ambient temperature (preferably around 36deg C), so condensation doesn't occur. More important than anything, you have to be sure to check over all your hookups and tubing weekly, to spot any possible problems before they sprout into leaks (overall danger isn't too much, provide you don't run too much pressure -- but better safe than sorry). Those pre-built kits, like the one you chose, are pretty nice because you don't have to worry much about messing up -- just that they don't mess up...
