FrostyTech has posted a review on the Dynatron Model-O Copper Microfin Heatsink

The Microfin technology used in the Model-O heatsink is quite simple from the outset. Small flaps of copper have been skived from a flat plate of copper to form fins which stand upright, creating a seamless thermal joint. With the Dynatron Model-O, both fins and base are made from one solid piece of copper - there are no joints whatsoever. The only component attached to the one-piece heatsink is the aluminum shroud used to support the fan, and direct airflow down into the fins.

Now we've seen similarly formed heatsinks before (ie. the aluminum AVC Skive), but so far none have had anywhere near the same degree of fin density. In fact the Model-O boasts sixty 0.35mm thick copper fins set at a pitch of 1.0mm. The high-density fin design creates a larger amount of surface area to diffuse heat to the surrounding environment, and should theoretically make this a more efficient heatsink.

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