Your 'argument about about D15 is untrue' for all the reasons above.Thing is i had for 3 1/2 years and seeing as them lovely people at Corsair give at a 5 year warranty i got a free upgrade replacement to a h100i pro also i wouldn't say a big air cooler is quieter, in fact far from it, i know because i removed a noctua nhd-15 because 1 it was too heavy and 2 it sounded like a jet engine and was audible even at lowest setting which evidently made the cooling worse compared to my 3 ml fans on front of the rad at 600rpm and pump on balanced is inaudible and way way quieter than what the nhd-15 so the argument about the noctua being quieter is not true
Interesting how you know CLCs are quiter than your NH-D15 based only on your skewed and poorly done use of D15. You obvioulsy had your NH-D15 in a system that was not supplying it needed room temp air it needed, and as a result it was using was much warmer than room and had to run it's fans at much higher speed to cool properly.
As for D15 being 'too heavy', can you supply any proof of it damaging anything? I doubt you can because I've never seen any damage resulting from using one.
Your '3 ml fans on front of readiator' are 3ml fans more likely additional airflow through case that was not there with D15.
Anyone can use a CLC. That is your choice. But the reality is a good air cooler cools as well as a CLC at similar abd lower noise levels, will last much, much longer and costs less money.