Help - what memory modules should I order for BlackOps motherboard?

[BazBell]

After updating my CPU to a Q6700 and finding my antiquated Foxconn motherboard is useless for OC it's made me want to upgrade it to a Foxconn BlackOps motherboard.

The BlackOps spec for memory says:- Memory: 4x DDR3 DIMM 1600 / 1333 / 1066 / 800 / 667MHz (Max. 8GB)

Simple question for you experts ... Should I just go for memory rated at 1600MHz like these?

http://www.overclockers.co.uk/showproduct.php?prodid=MY-043-GS

or is it worth going for memory modules rated at 2000MHz like these?

http://www.overclockers.co.uk/showproduct.php?prodid=MY-037-GS&groupid=701&catid=8&subcat=1387

or even 2133MHz like these?

http://www.overclockers.co.uk/showproduct.php?prodid=MY-083-GL&groupid=701&catid=8&subcat=1387