Don't make a to big fuzz about it.
I have a BIX, a heatercore and a double heatercore. Also a rad from astec (waterchill), one from a moped (pirelly), one from a motor cycle (honda), and one from my koolance set.
I also have a hydrocool, but I let that set intact.
You can say I collected quite some in my goal for perfection
The name of the game here is to match.
A heatercore is less restrictend with waterflow and airflow, but it is bigger.
For a heatercore (e.g. JR-120) you need to have a fan capable of flow, and not so much pressure, but nice silent (e.g. PAPST 4412)
For a BIX you need a fan capable of more pressure (Sunon or PAPST 4312 e.g.)
A heatercore will be more silent, as you can use more quiet fans.
But this also has to do with the rest of your setup.
I also have the MCP600, and it is as "silent" as a PAPST4312 at 12v.
So as you have the pump, the rest is just to match. Wat do you preffer to hear? Pump or fan...
Don't worry to much about the temps. the difference between a BIX and a heatercore with the right fan is not mesurable with my onboard sensor.
Lapping your Wite Water and CPU will

(I lapped them to 2500 grid)