I spent the last couple of days doing some sharpening, the sharpest knife, by a wide margin is also the least expensive (again by a wide margin).... A Mora by Erikkson (size #1). The second sharpest is the blade on my SAK which I reprofiled and stroped to a mirror polish. Third would be my full size spyderco calypso. Fourth would a FieldTrek by Allen Blade.
These three knives just blew away more expensive custom knives in terms of level of sharpness. Of course most of my customs (Busse, Rinaldi, Livesay) are much thicker, and therefore stonger. But for sheer cutting efficiency you cant beat a thin balde with a highly polished, very acute edge.