Custom water cooling:
It takes more effort to set up properly than building the PC itself. Plus it just looks plain retarded. I saw this one setup and it looked like he had goddamn milk in his PC. To put it simply, if you use this method of cooling your CPU, you're a basement dweller. Enough said.
AIO liquid coolers:
Not as retarded as custom liquid cooling; but they're still retarded nonetheless. They're a fucking gimmick. A glorious high quality air cooler can outperform these pieces of shit in both temperature and acoustics at a much lower price point. I'm pretty sure most people get these pieces of shit for aesthetic reasons. To be fair to AIOs, they at least get that right.
Air coolers:
Clearly the best. No hassle whatsoever. Near zero risk of anything going wrong. Plus, nothing looks more badass in your PC than a huge heatsink.
Get salty, liquidfags. Noctua master race.