You know, I asked someone the same question a few hours ago. Here is the response I got :
"well the ramsinks will only add another 10-30mhz max on the memory overclocking, and afterall you can buy your own heatsinks and put em on yourself! note though that the msi core hs/fan is one of the best out there, it also directs cool air toward the ram chpis." -12am
Gainward is Great too.
-Wesley