OCZ has managed to create another very unique and well performing series with the ReaperX. The 4 GB kit performs exeptionally well at the intended CL rating, but seems to lack the overclockablity we are used to from 2 GB kits. As the density is higher and the modules are still double sided, such limitations were expected however. It would have still been nice to see the memory manage more than 920 MHz at a looser timing, as some may want to hit that magical 500 MHz at a 1:1 divider. You may want to opt for the faster CL5 ReaperX kit instead, which can handle 500 MHz out of the box and only costs around 120 US Dollars.
The design of the spreaders looks great and surely does cool the memory better with than without, but it also adds several problems. You will not be able to fit four of them next to each other. OCZ has eliminated this problem by offering the ReaperX in 4 GB kits only. The second space related issue are the curved heatpipe which may not fit next to a large graphic card.
Overall the ReaperX has some impressive performance for a 4 GB Kit, but it is also by far one of the more expensive pairs of 2 GB memory on the market today as other 800 MHz CL4-4-4 kits start at around 85 US Dollars with traditional heatspreaders.