Increased complexity I just meant it's more things to fail. Rather than 1 fan failing, now there's two or more plus a pump plus the risk of leakage (and I don't know if there's a lifespan on the coolant, if it needs to be replaced or monitored).
The Silent PC Review review of the Kuhler has it hotter at the same noise level compared to a big tower cooler.
http://www.silentpcreview.com/article1214-page7.html
My definition of quiet though I think is different than many, my PC is quieter than people talking outside down the street, I can hardly tell the difference between on and off.