DriverHeaven have a look at three of the most popular CPU coolers Xigmatek currently offer; the HDT-S1283, the HDT-RS1283 "Red Scorpion" and the HDT-S1284 "Achilles".
A quote from the article:
>> XIGMATEK CPU Coolers Review
All three of the coolers are based on the same design and Xigmatek's Heatpipe Direct Touch technology, but each one targets a different user group. We will thoroughly examine all three of them in this review.
>> XIGMATEK CPU Coolers Review