RAID on the My Book World Edition II Options

I like the mirroring function (RAID 1) offered on the My Book World Edition II, but does the device allow your to configure the HD to not mirorr like the ShareSpace allows and then you get the fill use of the 4TB (without mirroring RAID0) I am looking at the 4TB and i do not want to eventually full the 2TB which is then mirrored to fill the 4TB and i find there is nothing i can do. thanks

The device allows you to strip as well as mirrored.,209,263