A Hammer?
From what i can see - you have all the hardware needed to be able to run 4 250gig drives - the only thing that can now hold you back - is the on board software. That could be configured on your device to only recognise 2 drives, or to only let you create small arrays, or anything like that. Youll find out when it arrives, but my gut feeling makes me think you'll be ok, its often right when it comes to computers and tells me when it wants curry and beer but i try and ignore that. It just wants to grow.
Butuz