If u check how clever they are, they normally spec 2x60g drives at a tad higher cost than a single 120g. Ofc that's within the same range.
Whichever way they cut this, it's still $775 for 250g.
64m cache - which is where the speed readings come from. If I were them I'd try and look at tech that'd make the whole drive a cache. Then it would sustain the speeds. I wouldn't mind better this is cos of an 8/psuedo-16bit controller.
Still $775 for 250g.