I can't say for sure, as I've never owned/lapped a SA. However, this review
shows the base of the silver arrow to be almost perfectly smooth, but convex in one plain. The convexness(?) could be intentional on Thermalright's part, or it may not be. My guess is that lapping would be a good thing, but don't expect more than a 2-4C gain. proper application of a good TIM is going to yield bigger margins.
I will be lapping my CPU in a week or twoEdited by Nnimrod - 11/8/11 at 12:41am