[Stripedown]

1. 360 is better, altough if you want a high performance rad you shouldnt get an EK but BlackIce or something.
2. EK DPC 4.0 (the swiftech only says 454 lph )
3. no, either get universal+ram heat sink or a full cover block
4. rad

 

[Stripedown]

Black Ice® GT Stealth 360 is better
thicker and higher fin density

 

[Stripedown]

I suggest Gentle Typhoon's, more silent and better airflow.