Wow! Even though the memory is officially advertised as a CL5 product, it works really great at CL4. With only around 2.25V required to go beyond DDR2-1000 @ CL4 this memory looks like it will be a great product for overclockers. The CL4 setting also seems to be a sweet spot that balances frequency and performance, since the CL3 setting just does not have enough clock headroom.
If you are set out to reach as fast clocks as possible, then use CL5 and see your memory easily break DDR2-1100. Not fast enough? Go for CL6 at well over DDR2-1200.
The price tag of $464 for a 2 GB kit seems to be justified and is well within range of other comparable memory kits.