Corsair is clearly a member of the school of thought that says larger heat spreader equals faster memory. And, despite the fact they only have standard timings, these sticks of RAM boast bigger coolers than other manufacturers' efforts.
This has been achieved by extending the cooler above the usually cramped memory slot area. Although this does afford the sticks with better cooling, DDR3 requires less power than its predecessor so this shouldn't be as much of a problem as it previously was.
When tested in operation, the XMS memory is surprisingly unexciting. The 9-9-9-24 timings are thoroughly standard, producing figures pretty much as expected.
As you'd expect, there is plenty of room for overclocking, but with the timings so high anyway, how far you can push these memory sticks is defined by the other components in your system. On the plus side, these sticks are tumbling in price, and they could soon offer much better value for money.