I've only used poorman's Intel ICHxR controller for RAID1. However, since my Intel RAID controller doesnt recognize my new 4TB HDD's, I have to software RAID them or spend considerably more money for a new HDD external enclosure with builtin RAID.
I have usually >40 simultaneous connections when downloading NZBs (for maintaining stable Internet speed from ISP), I am curious how much CPU resources it would consume when using software RAID 1 instead of integrated Intel MOBO ICH controller RAID 1.