I wouldn't use WDs in any kind of RAID, hw controller or otherwise. They just screw up firmware and error reporting too often.

I am discouraged from using Areca based on number of people who lose arrays on 2cpu.com. In general I would not use any hardware controller that doesn't obey to the Common Disk Format (DDF) so that you can use third-party software for recovery. Other controllers I would have more faith in but I found that Linux software RAID and the RAID-like functionality in FreeBSD's ZFS are superior for my needs anyway.

(note that this is real software raid, not the junk in the motherboard BIOS)