Hardware Canucks posted a review of the G.Skill PI 2x2GB PC3-12800 DDR3 Kit.

G.Skill has recognized this need for high performance 2x2GB kits of DDR3 memory and has sprinkled the pot with a PC3-12800 4GB kit with tight timings of 7-7-7. DDR3 memory frequencies have really started taking off but at much looser timings. The DDR3-1600 and 7-7-7 timing combination really is a steadfast combo that has been common for 2x1GB kits but is a little harder to find in 2GB density sticks. To top off these rather impressive specifications, G.Skill has added in a set of their new PI heat spreaders.

G.Skill PI 2x2GB PC3-12800 DDR3 Kit Review