For those of you who are using the Scythe Slipstream fans,
I would recommend to undervolt them at 5V.I am using the 1600 RPM ones (high) and once hooked up to the rad they were quite noisy. It is actually no the fan itself which is noisy, but because they are pushing lot of CFM, the air through the rad is doing quite some noise. Somemore, with my tj-07, once I closed the case, the grill at the bottom was also adding some noise as the fan are closed to it and again because of the turbulence created.
I am not a silence freak, but the noise was quite loud. Not a problem when gaming, but when just browsing, I don't need that much cooling and that much noise.
So I have undervolted them to 5V (just use a fan header to molex adapter and hook the + of the fan to the 5V of the molex instead of 12V).
Now they are running a 1050 RPM @ 5V and they are a lot (and I mean
A LOT) quieter.
I was a bit worry that the temp would be a lot higher (although max CPU@57*c and max GPU@50+*C I had some room to spare). But the temp have actually barely changed. There is max +1*C on the CPU when running P95, and 1-2*C on the GPU when running ATI tool
Below is some 40min running P95 and ATI tool together for maximum heat generated (I have GPU + CPU on the same loop), rad fans at 5V / 1050 RPM.

Very acceptable temperatures versus noise level which is like 10 times better than before. Now, the most noisy component in my rig during gamin are the GC caps which whistle during high load
I have also started to see what it would take to get to 3.6GHz from 3.2GHz. My CPU is a dude, I need to pump 1.54V idle / 1.49V load (CPU-z readings) to pass 30 min OCCT stress test
But even with the fan at 5V the temps are still acceptable at max 70*C (that's the max I am willing to go anyways). But I am not sure whether I will leave run it at this voltage as this doesn't really change anything in everyday use and everything is running much hotter (including my room).
Now I am thinking to solder a switch to have the possibility to switch the fans from 5V to 12V when gaming. But I am not sure it is very good for the PSU