The card which you are thinking about buying has a PCI-X connector. Does your motherboard have a PCI-X slot? If not, you'll need to check that the card will work in a standard 32-bit PCI slot. Even if it does, there will be part of the card connector which will extend beyond the PCI slot and you will need to ensure that it will not touch any motherboard components that might be sticking up just beyond the slot.
Although it's a bit more expensive, you ought to consider a true RAID which will still give you the option of running the disks independently (JBOD) or setting them up as RAID 1 or RAID 5 if you later have the need.
I've had a good experience with a 3ware 9500S-4LP card
http://www.ebay.co.uk/itm/AMCC-3Ware-9500S-4LP-SATA-Raid-Controller-128MB-4-Ports-/260741843796?pt=UK_Computing_ComputerComponents_InterfaceCards&hash=item3cb56ccb54. The vendor is open to offers. This too is a PCI-X card but it does work in a 32-bit PCI slot.
Good luck.