Thank guys, you're a great help. The Yate Loon already annoys me at the constant 1300 rpm that it chugs away at, can't even begin to imagine what 2800rpm of full blown fury would sound like to my sensitive ears.
I saw the X-Bit review but I never looked into the Noiseblockers enough - typical and stupid, I put too much emphasis on the conclusion and what fans received a gold award and which ones didn't so I almost completely ignored the Noiseblockers.
The larger Slip Streams have a relatively limited availability here in Switzerland (meaning I'd have to wait up to two weeks to receive one - obviously completely unacceptable
) but the Noiseblockers are well stocked. Now I pretty much have to decide between the PK2 and the PK3. I assume the PK2 would be enough, but it's difficult to say what voltage the PSU feeds the fans at certain temperatures, i.e. I don't know what the Yate Loon's 1300 rpm means in terms of voltage supplied.
And last tips before I go buy one of the two? Once again, you guys have been extremely helpful, thanks for taking your time to look into it, seriously appreciate it.