It looks like there is a new memory rating on the market from Patriot, Intel Extreme Masters which purports to be hand tested for perfect XMP compatibility as well as sporting a new heatsink design.  Timings of 11-11-11-27 for DDR3-2133 are rather impressive as is 9-9-9-24 at DDR3-1600 and Bjorn 3D managed to overclock it to 2300MHz.  They did question the default 3T setting of the DIMMs as they ran fine at 2T though trying for 1T at those speeds is not only pushing it but questionably useful for anything but an heavily overclocked i7 CPU.

"Nowadays, memory tends to be more of a battle over who can bin the tightest, as all IC’s shipping for the most part are pretty much the same. In the memory market it all comes down to how you can differentiate yourself from the same old stuff that we may see every day. Patriot has the new Viper 3 series which is what this kit is part of, and carrying the “Intel Extreme Masters” means it went through extensive testing to prove utmost compatibility with new DDR3 motherboards and XMP easy tuning."

Here are some more Memory articles from around the web:

Memory