running one near passive on a quadcore.
depends on application and how you want the sink to perform.
if your not a enthusist, just grab a true. With good fans, you wont be able to tell them apart.
But I would say, dayam Thermalright, stupid lazy bums who doesnt own 1 sink with a good flat base. Ask ruby what she did to her TRUE.
Lapping is highly recomended even on there flagship sink.
Just a note about xigmatec. There hot, reason is TRUE's bases arent FLAT and your not putting enough heat load on the true to make them shine.
Lap the base, and i still have yet to see a sink catch up to a true with a good heat source. IE, moderately clocked quadcore.