They are STK-S5's, at least the one's I've seen.
Asked about their specs here some time ago but didn't get a clear response.
Apparently they were made for Nunno and didn't have the logo on the top.
But the underside shots clearly show that they are from that particular Duncan range.
i'm gonna get me a set!!
Also, higher end Washburn guitars with Floyds, are actually Schaller made Floyds
and you can pick them up for less than $100, just have the Washburn logo.