The price/performance isn't there. Why would I spend more on something that doesn't cool as well and has to ability to leak fluid into my computer? I'd rather pick up a high end Noctua or Thermalright heatsink and call it a day. Even if the fans fail on a traditional HSF you still have a barrier of protection, the heatsink itself.
This is coming from someone who's about to rip out a cheap water cooling kit
and put back in a traditional HSF.