As mentioned a few posts up, I'm really starting to realise that a decent air cooler on the CPU will be just as good as a custom loop for gaming systems. In systems that will push the CPU 100% for extended periods or systems that are heavily overclocked then water will make a difference, but for mild OC'd gaming rig it's unnecessary.
GPU's are totally different. I'm a big fan of the Gigabyte Windforce cooler, but even that will be put in it's place with a full cover block within a custom loop (AIO on GPU's are a waste of time IMO).