RAID0 Drives and FreeNAS/unRAID

I have an R710 that came with a PERC6i RAID controller. Currently I have 6 x 2TB drives installed, and while I'm fine with that level of capacity, I'd like to run FreeNAS or unRAID and I'm unable to pass through the drives.

Short of replacing the PERC with an H200 or something similar, is it ill-advised to just put each drive in RAID0 and allow the software RAID to manage everything from there?