Performance/reliability benefit of add-on RAID card vs Intel onboard controller

[train_wreck]

Currently using the Maximum VI Formula board with 3 Intel 520 SSDs in RAID 0, and 2 WD 2TB blacks in RAID 1, with WIn7 x64. I have read that the included Intel "Rapid Storage Technology" RAID adapter is not a "true" hardware RAID implementation. Would I see any kind of benefit from going to a PCIe RAID card, performance or otherwise? HD tune currently reports 1134MB/s transfer rate on the SSD array, with max of 1479MB/s

 

[popatim]

you'd free up the cpu a % or two but thats about it.