Frosty has a review of the Thermalright Ultra-120 heatsink, and by the looks of the thermal test results, the Ultra-120 is the best of the bunch!

"The Ultra-120 heatsink extends Thermalright's position as one of the best low noise heatsink manufactures in the market. Yet the Thermalright Ultra-120 applies only fairly simple cooling technologies; a selection of U-shaped heat pipes, widely spaced aluminum cooling fins, and a low speed 120 mm fan which is user provided. The end result though is a large, and albeit balky heatsink, but one which can be operated very quietly while disbursing the high heat loads from modern-day dual core processors."